Food Safety Risk Assessment of NSW Food Safety Schemes

Transcription

Food Safety Risk
Assessment of NSW Food
Safety Schemes
March 2009
NSW/FA/FI039/1212
Note: Parts of this document were revised in December 2012 following peer review.
Contents
Executive summary ........................................................................................................... 6
Introduction.................................................................................................................... 12
Dairy food safety scheme ................................................................................................ 16
Meat food safety scheme ................................................................................................. 39
Plant products food safety scheme ................................................................................... 67
Seafood safety scheme .................................................................................................... 85
Vulnerable persons food safety scheme .......................................................................... 105
Egg food safety scheme ................................................................................................ 120
Risk assessment – Conclusion ........................................................................................ 137
Appendix 1: Microbiological and chemical hazards of concern .......................................... 138
Appendix 2: Australian food recalls (2004–2008) ........................................................... 161
Appendix 3: Australian foodborne illness outbreaks (1995–2008) ..................................... 164
Food Safety Scheme Risk Assessment
Page 1 of 189
Tables
Dairy food safety scheme
Table 1 – Pathogenic microorganisms detected in raw milk................................................ 17
Table 2 – Microbiological hazards in dairy products ........................................................... 18
Table 3 – Consumption of dairy products .......................................................................... 21
Table 4 – Summary of foodborne illness outbreaks attributed to dairy products and foods
including dairy as an ingredient........................................................................................ 23
Table 5 – NZFSA risk profile outcomes examining hazards in dairy products ....................... 28
Table 6 – Risk ranking for dairy products contaminated with Listeria monocytogenes .......... 29
Table 7 – Risk ranking of dairy products ........................................................................... 30
Table 8 – Microbiological hazards in livestock and poultry .................................................. 41
Table 9 – Consumption of meat and meat products in Australia ......................................... 45
Table 10 – Consumption of processed meats in Australia ................................................... 45
Table 11 – Summary of foodborne illness outbreaks attributed to all meat, meat products and
meat included as an ingredient (1995–2008) (including poultry, game meat and processed
meat products) ............................................................................................................... 46
Table 12 – Prevalence of microbiological hazards in Australian beef and sheep meat........... 48
Table 13 – Prevalence of microbiological hazards on retail chicken meat in NSW (2005–06) 50
Table 14 – Foodborne illness outbreaks of listeriosis from processed meats ........................ 52
Table 15 – Prevalence of Listeria monocytogenes in processed meats ................................ 52
Table 16 – NZFSA risk profile outcomes examining hazards in meat ................................... 54
Table 17 – Risk ranking for meat and meat products ......................................................... 55
Table 18 – Risk ranking for processed poultry meat products ............................................. 57
Table 19 – NZFSA risk profile outcomes examining hazards in poultry meat ........................ 57
Table 20 – NZFSA risk profile outcomes examining hazards in processed meats .................. 60
Table 21 – Risk ranking for processed meat products ........................................................ 61
Table 22 – Risk ranking for L. monocytogenes-contaminated processed meats ................... 62
Table 23 – Microbiological hazards associated with plant products ..................................... 67
Table 24 – Consumption of fruits and vegetables in Australia ............................................. 71
Table 25 – Summary of foodborne illness outbreaks attributed to plant products ................ 74
Table 26 – Risk ranking for plant products contaminated with Listeria monocytogenes ........ 78
Table 27 – Summary of international hazard identification studies for seafood .................... 85
Table 28 – Hazards in seafood and seafood products ........................................................ 86
Table 29 – Production volumes for seafood in Australia and NSW 2006–07 ......................... 88
Table 30 – Consumption of fish and seafood products in Australia ..................................... 90
Table 31 – Failure rate for imported seafood products (1998 – 2003) ................................. 90
Table 32 – Summary of Australian seafood testing results ................................................. 91
Table 33 – Summary of high mercury levels in NSW seafood ............................................. 91
Table 34 – Prevalence of L. monocytogenes in UK retail smoked fish ................................. 92
Table 35 – Summary of foodborne illness outbreaks attributed to seafood .......................... 94
Table 36 – Risk ranking for seafood products contaminated with Listeria monocytogenes .... 99
Table 37 – Seafood consumption required to reach reference doses for methylmercury .... 101
Table 38 – Summary of foodborne illness outbreaks attributed to food served to vulnerable
persons ........................................................................................................................ 109
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Table 39 – Institutional foodborne illness outbreaks as a percentage of all outbreaks ........ 110
Table 40 – Relative susceptibility to listeriosis for different sub-groups ............................. 113
Table 41 – Estimated cases of listeriosis for vulnerable population sub-groups for each food
category, based on US data ........................................................................................... 114
Table 42 – Hazards in the production of shell eggs and egg products ............................... 121
Table 43 – Prevalence of chemical residues in eggs ........................................................ 123
Table 44 – Prevalence of Salmonella in Australian eggs ................................................... 125
Table 45 – Consumption of eggs and egg products in Australia ........................................ 125
Table 46 – Summary of foodborne illness outbreaks attributed to eggs, egg products and
eggs used as an ingredient ............................................................................................ 126
Table 47 – Risk ranking for type and use of eggs ............................................................ 129
Table 48 – Top Salmonella serovars from major sources ................................................. 140
Table 49 – Characteristics of Salmonella ......................................................................... 140
Table 50 – Characteristics of Campylobacter ................................................................... 141
Table 51 – Characteristics of Staphylococcus aureus ....................................................... 142
Table 52 – Characteristics of Clostridium perfringens ....................................................... 143
Table 53 – Characteristics of Bacillus cereus ................................................................... 144
Table 54 – Characteristics of Listeria monocytogenes ...................................................... 146
Table 55 – Characteristics of Vibrio parahaemolyticus...................................................... 148
Table 56 – Characteristics of Shigella spp. ...................................................................... 149
Table 57 – Characteristics of pathogenic Escherichia coli ................................................. 151
Table 58 – Characteristics of Clostridium botulinum......................................................... 152
Table 59 – Characteristics of Yersinia enterocolitica......................................................... 153
Table 60 – Important Aspergillus, Fusarium and Penicillium species and their mycotoxins . 158
Table 61 – Recalls of dairy products between 2004 and 2008 .......................................... 161
Table 62 – Recalls of meat products between 2004 and 2008 .......................................... 162
Table 63 – Recalls of plant products between 2004 and 2008 .......................................... 163
Table 64 – Recalls of seafood products between 2004 and 2008 ...................................... 163
Table 65 – Foodborne illness outbreaks attributed to milk, dairy products and dairy products
used as an ingredient .................................................................................................... 165
Table 66 – Foodborne illness outbreaks attributed to meat, meat products and meat products
used as an ingredient .................................................................................................... 166
Table 67 – Foodborne illness outbreaks attributed to plant products ................................ 174
Table 68 – Foodborne illness outbreaks attributed fish and seafood products ................... 175
Table 69 – Foodborne illness outbreaks attributed to foods served to vulnerable persons .. 182
Table 70 – Foodborne illness outbreaks attributed to eggs, egg products and eggs used as an
ingredient ..................................................................................................................... 185
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Abbreviations
aw
Water activity
ABARE
Australian Bureau of Agricultural and Resource Economics
ABS
Australian Bureau of Statistics
ACMF
Australian Chicken Meat Federation
ACMSF
Advisory Committee on the Microbiological Safety of Food (UK)
AECL
Australian Egg Corporation Limited
ANZDAC
Australia New Zealand Dairy Authorities Committee (formerly
ADASC)
AMRA
Australian Milk Residue Analysis Survey
APL
Australian Pork Limited
APVMA
Australian Pesticide and Veterinary Medicines Authority
ASP
Amnesic Shellfish Poisoning
ASQAP
Australian Shellfish Quality Assurance Program
ATDS
Australian Total Diet Survey/Study
APVMA
Australian Pesticides and Veterinary Medicines Authority
AQIS
Australian Quarantine and Inspection Service
BSE
Bovine Spongiform Encephalopathy
BTEC
Brucellosis and Tuberculosis Eradication Campaign
CAC
Codex Alimentarius Commission
cfu
Colony forming unit
CFR
Code of Federal Regulation (US)
CJD
Creutzfeldt-Jakob Disease
DAFF
Department of Agriculture Fisheries and Forestry (Australian
Government) (formerly AFFA)
DFSV
Dairy Food Safety Victoria
DSP
Diarrhoetic Shellfish Poisoning
EFSA
European Food Safety Agency
EHEC
Enterohaemorrhagic E. coli
ERL
Extraneous Residue Limit
EU
European Union
FAO
Food and Agricultural Organization of the United Nations
FDA
Food and Drug Administration (US)
FRDC
Fisheries Research and Development Corporation
FRSC
Food Regulation Standing Committee
FSA
Food Science Australia
FSAI
Food Safety Authority of Ireland
FSANZ
Food Standards Australia New Zealand (formerly ANZFA)
FSIS
Food Safety and Inspection Service (US)
GAP
Good Agricultural Practices
GBR
Geographical BSE Risk
GHP
Good Hygienic Practices
GMP
Good Manufacturing Practices
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HACCP
Hazard Analysis Critical Control Point
HAV
Hepatitis A virus
HTST
High Temperature Short Time pasteurisation
HUS
Haemolytic Uremic Syndrome
ICMSF
International Commission on Microbiological Specifications for Foods
JECFA
Joint FAO/WHO Expert Committee on Food Additives
KP
Kanagawa phenomenon
MAP
Modified atmosphere packaging
MeHg
Methylmercury
ML
Maximum Level
MLA
Meat & Livestock Australia
MMWR
Morbidity and Mortality Weekly Report
MRL
Maximum Residue Limit
NARM
National Antibacterial Residue Minimisation program
NEPSS
National Enteric Pathogen Surveillance Scheme
NGSP
National Granuloma Submission Program
NRS
National Residue Survey
NZFSA
New Zealand Food Safety Authority
OC
Organochlorine
OP
Organophosphate
PHLS
Public Health Laboratory Service, UK
PIRSA
Primary Industries and Resources South Australia
PISC
Primary Industries Standing Committee
PSP
Paralytic Shellfish Poisoning
PTWI
Provisional Tolerable Weekly Intake
REPFEDS
Refrigerated processed foods of extended durability
RIRDC
Rural Industries Research and Development Corporation
RIS
Regulatory Impact Statement
RTE
Ready-to-eat
SARDI
South Australian Research and Development Institute
SSOP
Sanitation Standard Operating Procedures
STEC
Shiga toxigenic E. coli
SWG
Sector Working Groups
TFAP
Tuberculosis freedom assurance program
TVC
Total Viable Count
UCFM
Uncooked comminuted fermented meats
UHT
Ultra Heat Treated
USDA
US Department of Agriculture
WHO
World Health Organization
YMT
Yolk Mean Time
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Executive summary
The NSW Food Regulation 2004 contains food safety schemes that outline the
regulatory requirements for dairy, meat, plant products, seafood businesses and
businesses serving food to vulnerable persons in NSW. A draft egg food safety
scheme is currently being finalised for inclusion in the Regulation.
The regulatory requirements in the food safety schemes have been introduced over a
number of years, either by the NSW Food Authority or its predecessor organisation
SafeFood Production NSW. Dairy and meat food safety schemes were carried over
from previous legislation. Individual risk assessments were carried out prior to the
introduction of both the seafood and plant products food safety schemes. The
development of the vulnerable persons food safety scheme occurred following the
introduction of Standard 3.3.1 – Food Safety Programs for Food Service to
Vulnerable Populations of the Australia New Zealand Food Standards Code (Food
Standards Code). In respect to the egg food safety scheme, the NSW Food Authority
conducted a risk assessment prior to developing requirements for the scheme.
Within each sector covered by the food safety schemes there are a wide variety of
hazards that may potentially be present and cause illness in the consumer. The
degree of illnesses caused by these hazards can range from mild illness through to
severe and life threatening disease. In general, it is the microbiological hazards
associated with foods that are considered more significant, as chemical and physical
hazards are rarely detected in food.
This risk assessment document summarises the known information from previous
risk assessments, risk profiles and hazard assessments, and includes new or updated
information where it is available and applicable to food businesses in NSW.
In 2006–2007 there were 684 million litres of milk sold in NSW and ACT, with the
average person consuming in excess of 100 L of pasteurised milk each year.
A wide variety of bacteria may be present in raw milk with the microbial status of
milk being influenced by animal health, the farm environment and production
methods. Pasteurisation was successfully introduced to eliminate tuberculosis and
brucellosis from milk and nowadays the main microbiological hazards associated with
milk and dairy products include Salmonella, Listeria monocytogenes, pathogenic
Escherichia coli, Staphylococcus aureus, Campylobacter spp., Yersinia enterocolitica
and Cronobacter sakazakii.
Between 1995 and 2008 there were fourteen Australian outbreaks attributed to dairy
products, none occurring in NSW. Nine of these outbreaks were associated with
consumption of unpasteurised milk. Internationally, foodborne outbreaks associated
with dairy products have been attributed to the use of unpasteurised milk,
contaminated non-dairy ingredients, faulty pasteurisation process and poor hygiene.
Controlling the safety of milk and dairy products relies on using raw materials (milk
and non-dairy ingredients) of good quality, ensuring correct formulation, effective
processing, prevention of recontamination and maintenance of temperature
throughout the cold chain. Dairy products identified as high risk include
unpasteurised milk, soft cheese, dairy desserts, fresh cheeses and dairy dips, as
these products may support the growth of pathogenic microorganisms.
Two critical steps in controlling pathogens in milk and dairy products are effective
pasteurisation, followed by good manufacturing practices to ensure postFood Safety Scheme Risk Assessment
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pasteurisation contamination does not occur. Food safety programs targeting these
controls have been an effective mechanism for controlling microbial hazards in milk
and dairy products.
There are several potential sources of chemical contamination associated with milk
production including agricultural and veterinary chemicals, environmental
contaminants and chemicals from animal feed. The implementation of on-farm food
safety programs has managed these risks, and the risk is considered low as surveys
of dairy products have not detected significant levels of chemicals in Australian milk
and dairy products.
Meat food safety scheme
It has been estimated that Australians each consume 38.2 kg of beef and veal, 11.4
kg of lamb, 2.7 kg of mutton and 14.4 kg of bacon and ham products each year.
Various microbiological hazards are associated with different types of meats, with
Salmonella, pathogenic E. coli, Clostridium perfringens, Campylobacter jejuni and the
parasite Toxoplasma gondii associated with beef and sheepmeat, while the primary
pathogen of concern in pigmeat is Yersinia enterocolitica.
Livestock and poultry can serve as a reservoir for pathogenic microorganisms and
within the abattoir environment these pathogens can be transferred from the gut to
the external surfaces of the carcase and contaminate equipment and workers.
Currently the risk associated with red meat is considered low, due to the control
measures implemented by the meat industry, such as the Australian Standards for
the hygienic production of meat and game meat. However, cross contamination of
ready-to-eat (RTE) foods by raw meat is considered a potential issue of concern. It
has been estimated that if the cross contamination rate of Salmonella increased from
1% to 10% there would be an extra 5000 cases of foodborne illness, while an
increase to 50% would result in more than 29,000 cases of salmonellosis across
Australia each year.
Poultry is the most widely consumed meat in Australia, with each person consuming
39.5kg of poultry each year. The primary hazards of concern in poultry meat are
Salmonella and Campylobacter spp. Contamination of poultry can occur on farm
through breeding stock, contaminated water, litter, insects, rodents, wild birds and
farm workers. Surveys have identified poultry meat as a significant source of
foodborne illness, with 46 confirmed outbreaks and 1170 cases of illness between
1995 and 2002. Due to significant under-reporting, it is estimated that cases of
foodborne illness due to processed chicken products may be as high as 79,000 cases
per year. A through chain approach is the preferred option to reduce contamination
of poultry meat, with estimates that this could reduce levels of poultry-related
foodborne illnesses by between 74% and 93% each year.
Processed meat products have also been identified as high risk, with the pathogens
of concern including pathogenic E. coli, Salmonella and L. monocytogenes. There
have been a large number of recalls of processed meats due to L. monocytogenes,
and a significant number of foodborne illness outbreaks. Between 1991 and 2000,
323 cases of illness and one death were attributed to consumption of processed
meats with a total cost to the community estimated to be $77 million.
Controlling pathogens in processed meats include effective cooking, curing or
fermentation with starter culture, and implementation of good hygienic practices
(GHP) to limit the potential for post-processing contamination with
L. monocytogenes. Food safety programs have been widely implemented in the
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processed meat sector to ensure control measures are in place. However, it was
estimated that if these programs are not complied with, and poorly controlled or
unreliable processing was allowed to occur in the production of uncooked
comminuted fermented meats, this could lead to a significant increase in risk, with
estimates the number of foodborne illness cases in Australia due to pathogenic E. coli
could be up to 604 cases per year.
Plant products food safety scheme
Previous risk assessment work conducted on the risk associated with plant products
found that fresh cut fruit and vegetables, seed spouts, vegetables in oil and
unpasteurised juice present a high risk. This was due to a history of foodborne illness
outbreaks in Australia, mainly due to Salmonella, in addition to a number of
outbreaks overseas. Annual NSW consumption of these products has been estimated
as being 11,000 tonnes of fresh cut vegetables, 150 tonnes of fresh cut fruits, 2600
tonnes of seed sprouts, 1000 tonnes of vegetables in oil products, and 100,000 L of
unpasteurised juice.
Surveys of plant products have shown the potential for these high risk plant products
to be contaminated with L. monocytogenes, Aeromonas spp., B. cereus and
Salmonella.
Contamination of fresh cut fruit and vegetables can occur during growth, harvest or
processing with the main pathogens of concern being L. monocytogenes in general,
and C. botulinum for modified atmosphere packaged product. These products are
considered high risk when they are consumed raw.
Seed sprouts can become contaminated with B. cereus, Salmonella and pathogenic
E. coli during growth and harvest of the seeds and also during the sprouting process,
which provides a near perfect environment for the growth of microorganisms.
The oxygen reduced environment provided by vegetables immersed in oil allows for
the growth of anaerobic microorganisms including C. botulinum, the cause of
botulism. To reduce the risk, the vegetables or fruits are usually cooked and acidified
prior to placement in oil.
Unpasteurised fruit juices may become contaminated during the juicing process,
either due to contamination on the exterior of the fruit or the use of damaged and
mouldy fruit. Because the juice is not heat treated, any pathogenic microorganisms
present are able to survive, and acid tolerant strains of pathogenic E. coli and
Salmonella may grow.
Seafood safety scheme
Annual consumption of seafood has been estimated at approximately 15.1 kg per
person. The hazards associated with seafood vary depending on the type of seafood
and processing methods employed.
Shellfish, particularly oysters, as filter feeders can accumulate contaminants from the
growing environment. The hazards of concern for shellfish include pathogenic
bacteria and viruses, algal toxins and chemical contaminant from the growing
environment. Viral contamination of shellfish is recognised as the highest risk for all
seafood and is effectively managed by the implementation of shellfish safety
programs that manage the waterway and harvesting of the shellfish. Algal toxins in
shellfish are generally considered low risk where harvest management programs
manage the risk. Where no programs are in place, the risk associated with algal
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toxins increases to medium. Severe illness has been associated with the consumption
of oysters contaminated with V. vulnificus.
Wild caught prawns particularly those caught in estuarine waters are susceptible to
contamination from the environment, such as naturally occurring Vibrio spp. present
in the waterway. Prawns treated with metabisulphite may present a problem to
consumers who suffer from asthma-related conditions. The on-board cooking and
cooling of prawns also has the potential to introduce bacterial contamination when
water from the waterway is used to cool the prawns.
Hazards associated with wild caught finfish include ciguatera and histamine,
depending on the type of fish caught. Ciguatera poisoning is generally regarded as
medium risk, with most illnesses occurring with fish caught near tropical reefs.
Histamine poisoning is usually associated with certain fish such as tuna, swordfish,
mahi mahi and blue grenadier and can be controlled by effective temperature control
throughout the supply chain. If the fish are to be consumed raw, hazards such as
parasites and Vibrio spp. become significant. Mercury in finfish presents a risk to
pregnant women or women planning to become pregnant. Because mercury is
naturally present in the marine environment, management strategies have relied on
education of the consumer, in particular advising pregnant women to avoid
consuming large predatory fish which are known to contain higher levels of mercury.
Processed, RTE seafood products (including smoked seafood) can support the
growth of L. monocytogenes, however contamination is thought to occur during the
handling and packaging of the finished product. Strict hygiene and sanitation
programs can reduce the likelihood of contamination. The packaging of smoked
seafood under modified atmosphere packaging may allow the growth of
C. botulinum. While botulism poisoning associated these products is rare, the illness
is severe and is considered a medium risk.
Vulnerable persons food safety scheme
Certain population sub-groups are more at risk of foodborne illness or can develop
more severe conditions due to foodborne illness when compared to the general
population. The degree of vulnerability depends on the susceptibility of the individual
and the pathogenicity of the pathogenic microorganism. In general terms, the
vulnerable population group includes children under five years of age, people over 65
years old, pregnant women and persons with depressed immunity.
It is estimated that the number of meals served to vulnerable persons in NSW
facilities such as hospitals, aged-care facilities, hospices, day care establishments and
childcare centres is approximately 133 million meals per year. It is estimated that up
to one million meals per year served at these facilities may be contaminated with a
foodborne pathogen.
Since 1995 there have been 65 foodborne illness outbreaks in Australian aged-care
facilities, childcare centres and hospitals with 758 illnesses and 75 fatalities. The
pathogens implicated have included Salmonella, C. perfringens, L. monocytogenes
and Campylobacter. The prevalence of foodborne-related illness and deaths in the
elderly living in nursing homes is far greater than the baseline level of illness in
general population, while children appear more at risk to Salmonella due high
salmonellosis rate in children seen both in Australia and overseas.
The major hazard of concern to vulnerable persons is L. monocytogenes, with some
sub-groups within the vulnerable population being 100 times more susceptible to
listeriosis than the general population. Other hazards of concern include infants
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exposed to C. botulinum through consumption of contaminated honey, neonatal
infants consuming Cronobacter sakazakii (formerly Enterobacter sakazakii)
contaminated infant formula and individuals with liver dysfunction exposed to
Vibrio vulnificus via raw oysters. Other organisms that may result in more severe
illness in vulnerable sub-groups include pathogenic Enterohaemorragic E. coli,
S. aureus and C. perfringens.
When assessing the risk associated with foods, it is important to consider food
preparation and hazardous scenarios. Businesses catering to vulnerable persons need
to consider the susceptibility of their consumers when designing menus and
sourcing, preparing and serving foods. Under the Food Standards Code, these
establishments are required to implement a food safety program including,
substitution of high risk foods with lower alternatives; effective cleaning and
sanitation of fruits and vegetables to be consumed raw; limiting the storage of
reconstituted infant formula; minimising storage times/temperatures for RTE foods;
ensuring foods are cooked properly and effective cleaning and sanitation of
equipment.
Egg food safety scheme (draft)
The average Australian consumes approximately 137 eggs per year, equating to over
800 million eggs being consumed in NSW each year. The primary hazard of concern
is Salmonella, in particular Salmonella Typhimurium which may contaminate the egg
shell through environmental contamination and through contact with bird faeces.
Overseas foodborne illness outbreaks attributed to eggs have been predominantly
due to Salmonella Enteritidis however, Australian layer flocks remain free of
Salmonella Enteritidis.
While Salmonella may be present in the farm environment, surveys have found the
prevalence of Salmonella on shell eggs to be very low. However, eggs and egg
products can also become contaminated during the grading and processing due to
improper crack detection, incorrect washing of eggs and poor hygiene and sanitation
during the processing of eggs into pulp and other products. Although egg products
such as liquid pulp are pasteurised, the heat treatment is only mild and therefore it is
important to limit the level of microbiological contamination.
There is significant epidemiological evidence to suggest that a major contributing
factor of salmonellosis in Australia is the use of dirty and cracked eggs, especially in
products that receive minimal or no cook step. The Food Standards Code limits the
sale of cracked eggs to businesses where the egg will be further processed and
receive a heat treatment.
Depending on the hygienic practices on farm and proper grading, processing and
storage of eggs, the potential number of egg-related illnesses was estimated up to
1800 cases per year across Australia. Current industry practices to address these
issues include strict biosecurity on farm, implementation of quality assurance
systems during grading and processing and effective supply chain management.
Potential sources of chemical contamination of eggs on farm include contaminated
soil, insecticide spray, incorrect use of medication and inappropriate egg washing
solutions and concentrations. However, in general, only low levels of chemicals have
been detected in eggs and previous risk assessment has assessed the risk of
chemicals in eggs as low. The exception to this are specialty eggs such as Balut,
salted and century eggs, where surveys have detected the unauthorised use of lead
as an additive, leading to chemical contamination of some products. These products
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may also become contaminated with pathogens due to the extensive handling during
processing.
Conclusion
This review has illustrated that across the food safety schemes there are many
potential hazards that can impact on human health with microbiological hazards
considered the most significant. It concludes that for food businesses within these
schemes, mitigating food safety risks requires the development and implementation
of reliable, systematic and preventative procedures. Such procedures are the core
elements of food safety programs, introduced either due to regulatory requirements
or through industry-sponsored codes of practice. The review acknowledges that
mitigating food safety risk necessitates a multi-factorial approach extending beyond
the controls implemented by a food business operating under a food safety scheme.
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Introduction
Purpose
Under current legislation, the NSW Food Authority (the Authority) can establish food
safety schemes in respect to different type or classes of foods, food businesses or
food activity (Food Act 2003). The food safety schemes aims to assist in improving
the safe production and handling food by outlining the regulatory requirements for
the food, food businesses or food activity (or activities) covered by the scheme.
Currently food safety schemes exist for dairy, meat, plant products and seafood
businesses operating in NSW, as well as businesses serving food to vulnerable
persons. In addition to these schemes that have already been implemented, an egg
food safety scheme is currently being finalised.
These commodities have been identified as containing high risk products that may
potentially cause outbreaks of foodborne illness, and where the cost benefit analysis
justified a regulatory presence, and the use of regulatory tools such as the
implementation of food safety programs based on principles of Hazards Analysis
Critical Control Point (HACCP).
Current legislation also requires a risk assessment be undertaken when establishing a
new food safety scheme. The risk assessment provides the science to underpin the
food safety scheme and is required to be based on national or international
standards.
The Authority, or its predecessor SafeFood Production NSW, previously
commissioned risk assessment prior to the introduction of food safety schemes
relating to seafood and plant products. In addition, risk assessments were conducted
on the proposed scheme for egg and egg products and during the review of the dairy
food safety scheme. The requirements under the meat food safety scheme were
carried over from a previous legislation which did not require a risk assessment to be
conducted and as such the Authority has not previously conducted a risk assessment
in relation to meat. The vulnerable persons food safety scheme was introduced
following the gazettal of Standard 3.3.1 – Food Safety Programs for Food Service to
Vulnerable Populations of the Australia New Zealand Food Standards Code. Food
service to vulnerable populations were identified as high risk in the National Risk
Validation Project (Food Science Australia and Minter Ellison, 2002)
The purpose of this risk assessment document is to provide a scientific review of
hazards and their associated risks for food businesses covered by the food safety
schemes. This risk assessment summarises the known information from previous risk
assessment and where new or updated information is available, this has been
incorporated into the information.
Scope
This risk assessment will review the hazards associated with food businesses
regulated under the food safety schemes of the NSW Food Regulation 2004 and
includes:
•
Dairy
•
Meat
•
Plant products – fresh cut fruits and vegetables, unpasteurised juice and
vegetables in oil
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•
Seafood
•
Food service to vulnerable persons
•
Eggs and egg products (draft food safety scheme currently being finalised)
Overview of risk assessment
Risk assessment forms part of an overall process, called risk analysis. Risk analysis is
used by governments and industry to assess, manage and communicate the risk
associated with particular food or food groups and in turn aims to reduce the
potential for foodborne illness. The Codex Alimentarius Commission divides risk
analysis into three components (CAC, 1999):
•
Risk assessment – a process by which the potential risk posed by food safety
hazard(s) is determined
•
Risk management – the process of determining alternatives for control the
hazards identified in the risk assessment and
•
Risk communication – the exchange of information on risk and risk
management amongst interested parties.
CAC (1999) has identified four components of risk assessment:
•
Hazard identification – the process of identifying potential hazards associated
with the food
•
Exposure assessment – an estimation of the potential human exposure to the
hazard and includes the use of data such as the occurrence in the food
and/or potential consumption rates of the food
•
Hazard characterisation – the evaluation of the potential illness associated
with the hazard
•
Risk characterisation – the process of determining the probability of
occurrence and severity of the adverse health effects based on the
information collected in the hazard identification, exposure assessment and
hazard characterisation.
Previous risk assessment work
When developing a food safety scheme, the NSW Food Authority has previously
commissioned hazard assessments, risk profiles and risk assessments or sourced
information from risk assessments performed by other government and nongovernment organisations. These risk assessments have included:
•
Ross, T. & Sanderson, K. (1999). A risk assessment of selected seafoods in
NSW
•
Food Science Australia (2000). Final report – Scoping study on the risk of
plant products
•
Food Science Australia & Minter Ellison Consulting (2002). National risk
validation project. Final report
•
Miles, D. (2004). Risk assessment of the NSW dairy industry (unpublished)
•
Miles, D. and Chan, C. (2007). Risk profile and risk management of eggs and
egg products in NSW (unpublished)
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In addition, risk assessments have been conducted in Australia by other government
and non-government organisations. These include:
•
Sumner, J. (2002). Food safety risk profile for primary industries in South
Australia. Department of Primary Industries and Resources SA, Adelaide
•
FSANZ [Food Standards Australia New Zealand] (2002). Final assessment
report proposal P263. Safety assessment of raw milk very hard cooked-curd
cheeses. Food Standards Australia New Zealand Report
•
FSANZ (2006). A risk profile of dairy products in Australia. Food Standards
Australia New Zealand Report
•
MLA [Meat & Livestock Australia] (2003). Through chain risk profile for the
Australian red meat industry Part 1: Risk Profile
•
FSANZ (2005). Scientific assessment of the public health and safety of poultry
meat in Australia
•
FSANZ (2006). Public health and safety of poultry meat in Australia –
Explanatory summary of the scientific assessment, Canberra
•
MLA (2006) Listeria monocytogenes in smallgoods: Risks and controls
•
Ross, T. Walsh, P. and Lewis, T. (2002). Risk assessment of fish cold smoking
and marination processes used by Australian businesses. Biodevelopment
Consulting Pty. Ltd for SafeFood Production NSW
•
FSANZ (2005). Final assessment report, P265, primary production and
processing standard for seafood (Attachment 10)
•
Daughtry, B., Sumner, J. Hooper, G., Thomas, C. Grime, T., Horn, R., Moses,
A. & Pointon, A. (2005). National food safety risk profile of egg and egg
products. A report for the Australian Egg Corporation Limited (AECL)
Publication No 05/06 Project SAR-47
•
Thomas, C., Daughtry, B., Padula, D., Jordan, D., Arzey, G., Davey, K., Holds,
G., Slade, J., & Pointon, A. (2006). An egg: Salmonella quantitative risk
assessment model. AECL publication
Current approach
As there has been a considerable amount of risk assessment work already
undertaken on industries covered by the food safety schemes, the approach taken in
this document was to provide a review of previous work conducted. This information
has been supplemented with other more recently published information where
necessary (CAC, 2007). To minimise repetition, information common to the different
food safety schemes has been placed in the appendices to the document:
•
Appendix 1 – Common microbiological and chemical food safety hazards
•
Appendix 2 – Food recalls in Australia
•
Appendix 3 – Foodborne illness outbreaks in Australia
A number of methods have been used to estimate the level of exposure to hazards.
The approaches used include production data, consumption data, imported foods
testing failures, recalls, epidemiological data and results of food surveys. When
considering exposure the fate of the hazard during processing and preparation must
be taken into account.
Page 14 of 189
References
CAC [Codex Alimentarius Commission] (1999). Principles and guidelines for the conduct of
microbiological risk assessment. CAC/GL-30. Retrieved 14 October 2008, from
http://www.codexalimentarius.net/download/standards/357/CXG_030e.pdf.
CAC [Codex Alimentarius Commission] (2007). Working principles for risk analysis for food
safety for application by governments. CAC/GL 62/2007. Retrieved 22 December 2008, from
http://www.codexalimentarius.net/download/standards/10751/CXG_062e.pdf.
Food Act 2003, New South Wales Government (2008).
Food Regulation 2004, New South Wales Government (2008).
Food Science Australia & Minter Ellison Consulting (2002). National risk validation project.
Final report 2002.
Page 15 of 189
Hazard identification
The safety of milk and milk products has been extensively reviewed by regulatory
agencies in Australia and internationally. A large number of risk assessments and risk
profiles have been undertaken, examining the risks across the entire dairy supply
chain and conducting in-depth evaluations of specific pathogen-product
combinations. This risk assessment will summarise the major body of relevant work
undertaken to date.
In 1999, the former NSW Dairy Corporation commissioned Food Science Australia to
review the food safety systems that had been implemented in the NSW dairy
industry (Jansson et al, 1999). The report included a brief risk assessment and
endorsed the preventative approach to food safety through the implementation of
HACCP-based food safety programs throughout the dairy supply chain. This was later
updated in 2004, when the NSW Food Authority completed a qualitative risk
assessment of the NSW dairy industry which examined the microbiological and
chemical hazards along the dairy supply chain (Miles, 2004). This was developed as
an internal document to provide scientific rigour to the updated dairy food safety
scheme and provide a basis for determining the priority classification for segments of
the industry. In 2002, Primary Industries and Resources South Australia (PIRSA)
commissioned a food safety risk profile on primary production, including milk and
dairy products (Sumner, 2002). This report highlighted consumption of raw
(unpasteurised) milk as a high risk activity.
In 2006, Food Standards Australia New Zealand (FSANZ) undertook a comprehensive
risk profile of dairy products in Australia to inform the development of the Primary
Production and Processing Standard for dairy products (FSANZ, 2006). The FSANZ
risk profile examined both microbiological and chemical hazards. The findings of the
FSANZ risk profile are reported here.
Microbiological hazards
A wide range of microbiological hazards may be introduced into milk during primary
production and processing. Raw milk may have a diverse range of bacteria present in
it, either shed directly into the milk from the udder as a result of illness or disease, or
through contamination from the external surface of the cow and the milking
environment. FSANZ (2006) highlighted the on-farm factors that most significantly
impact on the microbiological quality of raw milk as:
•
animal-related factors (eg animal health, herd size, age and production
status)
•
environmental factors (eg housing, faeces, feed, soil, and water)
•
method of milking, operation of milking and storage equipment (eg
cleanliness of equipment and lines, appropriate storage temperature to limit
pathogen growth)
The initial levels of bacteria in raw milk can vary considerably, dependent on the
level of control over these factors. Boor (1997) reviewed the different types of
pathogenic microorganisms that have been detected in raw milk (Table 1).
Page 16 of 189
Table 1 – Pathogenic microorganisms detected in raw milk
Microorganism
Enterobacteriaceae
pathogenic Escherichia coli (eg EHEC, STEC)
Disease
Salmonella
Shigella
Yersinia enterocolitica
Cronobacter sakazakii
Gastroenteritis, other complications
involve Haemolytic uraemic
syndrome (HUS) and Thrombotic
thrombocytopenic purpura (TTP)
Gastroenteritis, typhoid fever
Dysentery
Gastroenteritis
Meningitis in premature infants
Campylobacter jejuni
Aeromonas hydrophila
Gastroenteritis
Gastroenteritis
Pseudomonas aeruginosa
Brucella spp.
Gastroenteritis
Brucellosis (Bang’s Disease)
Bacillus cereus
Bacillus anthracis
Clostridium perfringens
Clostridium botulinum
Gastroenteritis
Anthrax
Gastroenteritis
Botulism
Staphylococcus aureus
Streptococcus agalactiae
Streptococcus pyogenes
Streptococcus zooepidemicus
Emetic intoxication
Sore throat
Scarlet fever/sore throat
Pharyngitis, nephritic sequelae
Listeria monocytogenes
Corynebacterium spp.
Mycobacterium bovis
Mycobacterium tuberculosis
Mycobacterium paratuberculosis
Listeriosis (various manifestations)
Diphtheria
Tuberculosis
Tuberculosis
Johne’s disease (ruminants)
Crohn’s disease (unproven in
humans)
Vibrionaceae and Campylobacter
Other Gram-negatives
Gram-positive sporeformers
Gram-positive cocci
Miscellaneous Gram-positives
Rickettsia
Coxiella burnetii
Viral
Enteroviruses, including polioviruses and Coxsackie
virus, Rotaviruses
Foot and mouth disease virus
Hepatitis virus
Fungi
Mould (and associated aflatoxins)
Protozoan parasites
Cryptosporidium parvum
Entamoeba histolytica
Giardia lamblia
Toxoplasma gondii
Q fever
Enteric infection
Foot-and-mouth disease
(not a human disease)
Infectious hepatitis
Mycotoxicoses
Cryptosporidiosis
Amoebiasis
Giardiasis
Toxoplasmosis
adapted from Boor (1997)
Page 17 of 189
In the past, prior to the introduction of mandatory pasteurisation for milk in
Australia, the most important human diseases disseminated by the consumption of
raw milk were tuberculosis and brucellosis. These diseases have now been
eradicated in Australian dairy cow herds. As a result, the FSANZ risk profile (FSANZ,
2006) went on to identify the most significant pathogenic microorganisms to public
health and safety for the Australian dairy industry (Table 2). Further details on these
microbiological hazards are available in Appendix 1.
Table 2 – Microbiological hazards in dairy products
Pathogens
pathogenic Escherichia coli
Significance in dairy products
Pathogenic strains of E. coli can be found in cattle and may enter milk
through faecal contamination. Is destroyed by pasteurisation
Salmonella
Salmonella is occasionally present in raw milk but is destroyed by
Campylobacter spp.
Bacillus cereus
(formerly Enterobacter
sakazakii)
pasteurisation. Can contaminate products after pasteurisation, with nondairy ingredients a source of contamination. Frequently isolated in milk
powder
Y. enterocolitica is destroyed by pasteurisation and its presence in heat
treated milk products is due to environmental contamination after heat
treatment. Y. enterocolitica is able to grow in dairy products held at
refrigeration temperatures and therefore may be considered as a hazard
in prolonged shelf life products
Campylobacter spp. is destroyed by pasteurisation and its presence in
milk products is due to environmental contamination after heat treatment.
Not normally able to grow in foods
Vegetative cells of B. cereus do not survive pasteurisation, however
spores will survive. B. cereus is rapidly outgrown by psychrotrophic
bacteria at refrigeration temperatures. However, in the absence of a
competitive microflora, growth to levels of concern is possible
Vegetative cells of C. botulinum do not survive pasteurisation, however
spores will survive. Will only grow under anaerobic conditions
May enter raw milk through udder infection. S. aureus is destroyed by
pasteurisation, however toxins are heat stable. S. aureus does not grow
well at refrigeration temperatures or compete with starter cultures
L. monocytogenes is destroyed by pasteurisation. Its presence in dairy
products is due to post-pasteurisation contamination. Can grow in milk
products at refrigeration temperatures
C. sakazakii will not survive pasteurisation. Recontamination of powdered
infant formula during manufacture is a risk. C. sakazakii cannot grow in a
dry substrate, but it can survive for long periods of time and is a potential
hazard when the powder is reconstituted and held at favourable
temperatures. Contamination and subsequent growth may occur during
reconstitution and preparation
adapted from FSANZ (2006)
These hazards were considered significant due to either:
•
association with reported incidents of foodborne illness (including overseas
outbreaks), or
•
the potential to contaminate dairy products after pasteurisation.
This conclusion is supported by other work, such as that by Todd & Harwig (1996) in
a risk analysis of Canadian food, who stated that although 21 microbial hazards have
been reported to occur in Canadian milk, only eight of those presented a significant
risk to the human population, with Campylobacter jejuni, Salmonella serovars and
E. coli O157:H7 identified as the most important hazards. Johnson et al (1990)
identified Salmonella, Listeria monocytogenes and pathogenic E. coli as the three
Page 18 of 189
high risk organisms to the cheese industry in the USA. While, more recently, the
presence of Cronobacter sakazakii in infant formula has presented a significant risk
to premature infants (Lai, 2001; FDA, 2002; Himelright et al, 2002).
Chemical hazards
Chemicals are used by the dairy industry for a number of purposes, including pest
and weed control on farm, animal health and sanitising equipment. As a result, milk
may be susceptible to chemical contamination if proper controls are not in place. The
FSANZ risk profile evaluated the following potential chemical hazards (FSANZ, 2006):
•
agricultural and veterinary chemical used in dairy primary production
•
environmental contaminants, including heavy metals, organic contaminants
and micro nutrients
•
naturally-occurring chemicals found in plants or in fungi or bacteria
associated with plants which may be ingested by grazing cattle
•
food processing by-products
•
food additives, processing aids, and those chemicals that may migrate from
packaging into dairy products
Dairy products must comply with Standard 1.4.1 – Contaminants and Natural
Toxicants and Standard 1.4.2 – Maximum Residue Limits of the Food Standards
Code. These Standards sets out the Maximum Levels (MLs) of specified metal, nonmetal contaminants and natural toxicants and the Maximum Residue Limits (MRLs)
for agricultural and veterinary chemical residues present in food respectively.
Agricultural and veterinary chemical hazards
Without appropriate controls and the observance of appropriate withholding periods
for treated dairy cattle, it is possible for residues of these chemicals to occur in raw
milk. In Australia, the Australian Pesticide and Veterinary Medicines Authority
(APVMA) is responsible for registering agricultural and veterinary chemical products,
granting permits for use of chemical products and regulating the sale of agricultural
and veterinary chemical products. Veterinary chemicals administered to dairy cattle
are mainly antimicrobials and endo- and ectoparasiticides. Other veterinary chemical
uses include reproductive therapy and use of anti-inflammatory drugs or
anaesthetics. If the cow is lactating, then the product must specifically state that it
can be used in lactating dairy cows, and a milk withholding period may be specified.
The use of environmentally persistent pesticides, such as organochlorines, still poses
a potential problem for grazing animals. Potential hazards include excessive levels of
herbicides, pesticides or fungicides. Cereals and treated seeds used as animal feed
supplement are the most likely source of these contaminants, with the most
significant hazard to human health being those chemicals that can accumulate in
animal tissues or are excreted in the milk.
Aflatoxins
Grain crops can become contaminated with biological toxins, such as aflatoxins, a
group of extremely toxic metabolites produced by the fungi Aspergillus flavus and
Aspergillus parasiticus. When these moulds are allowed to germinate and grow on
harvested seed crops, the aflatoxins can be formed and ingested by dairy cattle
during feeding, eventually contaminating the milk. Aflatoxin contamination of milk is
more common in Europe where intensive supplementary feeding of dairy herds is
Page 19 of 189
conducted. In Australia, where herds predominantly graze on pasture, aflatoxin
contamination has not been reported (ANZFA, 2001).
Cleaning chemicals
Milking premises and equipment must be cleaned and sanitised to prevent the risk of
contaminating the milk with microbiological pathogens. However, overuse of these
chemicals can in itself create a hazard with the risk of chemical residues being left on
equipment. All chemicals used in detergents and sanitisers have the potential to
leave a residue on the dairy equipment surface if not used in the correct manner.
Physical hazards
The probability of introduction on farm of physical hazards which end up in the final
product is thought to be minimal. Any physical hazard contamination that may be
introduced on farm should be removed at the farm level. Most dairy farms include a
filter ‘sock’ through which the milk passes prior to entering into the farm vat. This
filter will remove most gross physical contaminants.
The introduction of physical hazards at the processing level has occasionally
happened in the past, with pieces of equipment ending up in a dairy product. The
instances of this occurring are very rare, and the preventative maintenance of
equipment means the risk is very low. Good manufacturing practices and staff
training should also ensure that the risk of physical contaminants through the
wearing of personal effects such as jewellery are minimal.
Exposure assessment
Consumption of pasteurised milk and dairy products
Consumption of milk and milk products forms a significant part of the average
Australian’s diet. Standard 4.2.4 – Primary Production and Processing Standard for
Dairy Products of the Food Standards Code requires all milk for human consumption
(including milk used to make dairy products) to be pasteurised at a minimum of 72°C
for 15 seconds (or equivalent), unless an applicable law of a State or Territory
provides an exemption 1. There is no such exemption for cows milk in NSW, therefore
all dairy products for human consumption commercially sold in NSW are made from
pasteurised milk. In 2006/07, 684 million litres of milk were sold in NSW/ACT,
including modified and flavoured milk. Data from Dairy Australia shows the average
consumption of dairy products in Australia each year is 103.6 L milk, 11.9 kg cheese,
6.8 kg yoghurt and 3.9 kg butter/blends per person (Dairy Australia, 2007). A closer
analysis of consumption trends is shown in the Australian National Nutrition Survey
(ABS, 1995), which showed that 84% of people surveyed consumed dairy products
at a median amount of 347 g/day with the quantity ranging from 209–471 g/day
(Table 3). Consumption of dairy products varies with age, declining from 98% for
children aged 2–3 years to 90% for adults aged 19–24 years and then increasing
again to 95% for persons aged 65 years and over.
1
Standard 4.2.4A – Primary Production and Processing Standard for Specific Cheeses of the Food Standards Code
does allow imported Gruyere, Sbrinz, Emmental and Roquefort to be made from raw milk.
Page 20 of 189
Table 3 – Consumption of dairy products
Sex
Age
Male
Male
Male
Male
Male
Male
Male
Male
Male
Female
Female
Female
Female
Female
Female
Female
Female
Female
2–3
4–7
8 – 11
12 – 15
16 – 18
19 – 24
25 – 44
45 – 64
65+
2–3
4–7
8 – 11
12 – 15
16 – 18
19 – 24
25 – 44
45 – 64
65+
Proportion of persons
consuming milk products
and dishes 2
(%)
98.2
95.5
90.9
92.8
94.2
89.1
93.7
91.3
94.5
98.1
96.0
93.3
90.8
87.3
90.1
94.3
94.7
95.6
Median daily intake per
consumer of milk products and
dishes
(g/day)
471.8
365.0
401.4
424.0
392.2
323.0
263.2
258.0
255.0
394.3
280.5
312.0
297.7
258.0
251.3
209.3
216.6
225.8
adapted from National Nutrition Survey (ABS, 1995)
Liquid milk accounts for approximately 70% of the mean daily intake of dairy
products for persons of all ages. However, the trend of milk consumption within
Australia has been changing to more specialty types. Whole milk accounts for around
56% of milk sales, with lower fat lines increasing to 26%, long life or ultra high
temperature (UHT) treated milk 8.5%, and the remainder as flavoured and specialty
milks (Dairy Australia, 2007). Cheese consumption in Australia has jumped more
than 20% in the past decade. The recent consumer trend has been away from
cheddar cheeses to non-cheddar cheese types, and this is also being reflected in
Australia’s cheese exports, where the non-cheddar share of total export sales has
increased from 45% to 57% over the past seven years.
Consumption of raw milk
The current Dairy food safety scheme in the Food Regulation 2004 does not provide
an exemption from the requirement to pasteurise cows milk sold for human
consumption. However, no such limit exists on the private consumption of raw cows
milk. This is believed to be limited to small communities in NSW, such as farm
families. The amount of raw milk consumed on farm within NSW is difficult to
estimate, but is considered to be extremely small when compared to the volume of
pasteurised milk. The US Food and Drug Administration (FDA) and US Department of
2
Milk products and dishes are defined in the National Nutrition Survey (ABS, 1995) as including the following:
- Dairy milk
- Yoghurt
- Cream
- Cheese
- Frozen milk products (eg ice -cream)
- Other dishes where milk or a milk product is the major component
- Milk substitutes (eg soy-based milk)
- Flavoured milks
Page 21 of 189
Agriculture (USDA) in its quantitative risk assessment on listeriosis estimated raw
milk consumption to be less than 0.5% of total milk consumption in the USA
(FDA/USDA, 2003). Todd & Harwig (1996) made the assumption that ‘farm families’
were the people most likely to consume unpasteurised dairy products and
consequently be exposed to the microbiological hazards that may contaminate raw
milk.
The dairy food safety scheme does provide an exemption to allow the sale of
unpasteurised goats milk in NSW. This was initially a continuation of the permit
system implemented by NSW Health. The former SafeFood NSW commissioned a risk
assessment (AgriQuality New Zealand, 2002), but the authors could not fully
determine the risk from unpasteurised goats milk due to a lack of data.
Recommendations from the risk assessment report included the implementation of
HACCP-based food safety programs and a microbiological survey of unpasteurised
goats milk to generate data to provide the basis for a risk assessment. The National
Nutrition Survey (ABS, 1995) estimated that less than 1% of respondents consumed
goats milk and there is no evidence to suggest this has increased in recent years. In
fact the number of licensed goat milk producers in NSW has declined.
Recently ‘cosmetic’ and ‘bathing’ raw milk products have become available for sale in
NSW and other states. Although marketed for non-food use, it is believed these
labelling terms are being used to bypass the Food Standards Code, and that these
products are being consumed. While the volume consumed is considered to be very
small, the products are potentially unsafe. As such, the NSW Food Authority has
taken enforcement action when these products have been identified in the
marketplace, as they do not comply with the Food Standards Code requirements for
pasteurisation of cows milk for human consumption.
FSANZ are currently considering Proposal P1007 – Primary Production & Processing
Requirements for raw milk products. The outcome of that process could influence the
volumes of unpasteurised dairy product offered for sale in Australia.
Hazard characterisation
Foodborne illness outbreaks from milk and dairy products
Australian dairy products enjoy a reputation for high standards of quality and safety.
There have been few reported failures leading to incidents of foodborne illness
attributed to dairy products in the market place in recent years. FSANZ reviewed the
foodborne illness data associated with milk and milk products in Australia (FSANZ,
2006). This data is summarised in Table 4, with more detailed information on each
outbreak included in Table 65 (Appendix 3). Between 1995 and 2008 there were 14
reported outbreaks directly attributed to specific dairy products, affecting 284
people. Of these, nine were associated with consumption of unpasteurised milk and
none occurred in NSW. In addition, there were 12 outbreaks identified involving a
food product that contained dairy products as an ingredient. However, because dairy
products are an ingredient in many foods, it is often difficult to determine whether
they are the actual cause of an outbreak.
There have been a number of reports of outbreaks associated with consumption of
dairy products overseas. While unpasteurised dairy products have been a common
cause of dairy-associated outbreaks of illness, pasteurised dairy products have also
been implicated where there have been poor food safety control measures in place,
including the use of contaminated non-dairy ingredients, faulty pasteurisation
process, poor hygiene or contamination post pasteurisation.
Page 22 of 189
Table 4 – Summary of foodborne illness outbreaks attributed to dairy products
and foods including dairy as an ingredient
Hazard
Salmonella serovars
Campylobacter
Norovirus
C. perfringens
Chemical contamination
Cryptosporidium
S. aureus
Unknown
Total
Australian
outbreaks
(1995–2008)
7
6
3
1
1
1
1
6
26
Cases
226
85
123
27
23
8
2
86
582
Hospitalisations Deaths
5
0
0
0
0
3
0
1
10
0
0
0
0
0
0
0
0
0
While there is little corresponding evidence in Australia linking consumption of
pasteurised dairy products to foodborne illness, the potential impact of a dairyrelated food poisoning outbreak due to the widespread consumption of dairy foods
has been demonstrated by some large scale foodborne illness outbreaks overseas. In
2000, over 13,000 people were sick and 165 people hospitalised in Japan following
consumption of dairy products made by the Snow Brand Milk Products Co. that were
contaminated with S. aureus enterotoxin (Asao, 2003). In addition, the 2008
deliberate adulteration of Chinese milk with melamine resulted in worldwide recalls of
dairy products and a wide range of other foods where milk powder was used as an
ingredient. The broad distribution of Chinese milk powder graphically demonstrated
that a food safety incident in one country can have international repercussions and
encompass a broad spectrum of products.
Shiga toxigenic Escherichia coli (STEC) in raw milk
Cattle have been identified as an important reservoir for pathogenic E. coli, and
although pasteurisation does eliminate E. coli, outbreaks of E. coli O157:H7
infections overseas have been attributed to contaminated raw milk and some
pasteurised dairy products. A 1998 Australian study examined the incidence of STEC
in dairy cattle on four farms, with evidence of STEC detected in the faeces of 39% of
the 843 cattle tested (Desmarchelier, 1998). The prevalence rates varied between
farms, although generally milking cows had a lower rate (24%) than younger
animals (33–41%). The STEC isolated from dairy cattle included E. coli O157:H7
(0.9%) and E. coli O26 (0.16%), both known pathogenic serotypes.
However, when the prevalence of STEC in Australian raw milk was assessed, it was
found to be relatively low (Desmarchelier, 1998), with STEC isolated from 27 of
1,802 samples (1.5%). It was hypothesised that low level carriage may normally be
present in the dairy herd and this is periodically stimulated by some host or
environmental factor. It appears that during these episodes of increased faecal
shedding, there is an increase in environmental contamination and associated
increased risk of milk becoming contaminated.
Salm onella in dairy products
The first significant case of Salmonella in an Australian milk product occurred in 1943
in Victoria. A typhoid-carrying farm worker contaminated raw milk, which was then
distributed for public consumption, resulting in over 400 cases of typhoid fever and
Page 23 of 189
23 deaths (Merrilees, 1943). Since that time, there has been only one other major
incident involving Salmonella in pasteurised dairy products. This occurred in Victoria
in 1977 and was traced to milk powder becoming contaminated due to contaminated
lining of the spray dryer (Forsyth et al, 2003). The former Australian Dairy
Authorities’ Standards Committee (now ANZDAC) produced the Australian manual for
control of Salmonella in the dairy industry (ADASC, 1999b) to specify control
measures for limiting the risk of dried milk products becoming contaminated with
Salmonella.
Yersinia enterocolitica in milk
Y. enterocolitica has been isolated from raw and pasteurised milk in various parts of
the world. Although some strains occasionally associated with human disease have
been isolated from raw milk, the main pathogenic types generally do not
predominate. Milk has been associated with sporadic cases and outbreaks of
Y. enterocolitica infections overseas where milk was contaminated postpasteurisation by contact with implements contaminated by milk crates used on
piggeries (Barton & Robins-Brown, 2003). A suggested, though not proven, link
between human yersiniosis and pasteurised milk in NSW has been reported (Butt et
al, 1991).
Cam pylobacter spp. in milk
Both Campylobacter jejuni and Campylobacter coli are found in the faeces of cattle
and can cause cases of subclinical mastitis. Hutchinson et al (1985) reported a milkborne outbreak resulting from the consumption of raw milk from cows exhibiting no
outward evidence of illness. Healthy lactating cows can carry C. jejuni in the
intestinal tract, providing an extrinsic source of contamination. In one US study of
193 healthy dairy cows at three dairies, 77 (40%) had positive rectal cultures (Martin
et al, 1983).
Overseas surveys of Campylobacter in raw milk have shown a prevalence of 1 to 6%
(Wallace, 2003). Campylobacter is killed by pasteurisation. However, these
organisms are unlikely to grow in milk or dairy products. Nevertheless, several
outbreaks of Campylobacter food poisoning from consumption of raw milk in
Australia have been reported among children who were taken on a class trip to a
dairy and given raw milk to drink.
Bacillus cereus in liquid milk
Raw milk is frequently contaminated with Bacillus spp. spores, with the milk often
contaminated at the farm. Sanitation of the teats prior to milking was able to reduce
the incidence of B. cereus in raw milk (Christiansson et al, 1999). The presence of
B. cereus in a processed dairy product is often associated with the ability of the
spores to survive pasteurisation, after which the resulting vegetative cells may
colonise pipes, tanks and filling machines (Lin et al, 1998).
Notermans et al (1997) examined the risk from B. cereus in pasteurised liquid milk in
the Netherlands. The study estimated that up to 7% of pasteurised milk may contain
B. cereus, with levels ranging up to 105 cfu/mL.
In Australia, pasteurised milk has not figured as a cause of B. cereus food poisoning.
Clostridium botulinum in dairy products
Dairy products have not traditionally been associated with outbreaks of botulism.
Since 1912 fewer than 12 outbreaks associated with dairy products worldwide have
been recorded (Szabo & Gibson, 2003). However, spores of C. botulinum survive the
Page 24 of 189
normal milk pasteurisation process, and therefore control factors such as aw (water
activity), redox potential, pH and temperature must be used in dairy products such
as cheeses and dairy-based spreads and sauces to reduce the risk of botulism.
In 2007, one case of botulism was reported in Victoria and was associated with the
consumption of a nationally distributed ready-to-eat nachos meal. The neurotoxin
was detected in discarded remains of that meal pathogen (OzFoodNet Working
Group, 2007). One of the components was a cheese sauce and subsequent
laboratory testing showed that the sauce provided an environment that would
support growth of the organism. This case is not included in Appendix 3 data as it
was not classed as an outbreak, affecting only one person.
Botulism in dairy herds is caused by ingestion of preformed toxins produced by the
growth of C. botulinum in decaying crops, vegetation or carcase material, or by the
animal acquiring a gastrointestinal infection with the organism. The presence of
neurotoxin in milk from animals diagnosed with botulism is periodically raised as a
concern. When these incidents occasionally occur in dairy herds in Australia, farmers
voluntarily remove affected animals from supplying milk. There is little evidence in
the scientific literature to suggest the transfer of botulinum neurotoxins or the
organism itself to milk occurs from either symptomatic or asymptomatic animals in
affected herds.
Staphylococcus aureus in milk
S. aureus is a cause of mastitis in milk producing animals and can be frequently
found in raw milk from cows with undetected mastitis. Even in subclinical cases of
mastitis up to 105 cfu/mL of S. aureus can be shed into the milk. S. aureus is a poor
competitor, and will not grow well in the presence of other bacteria commonly
present in raw milk. However, it is believed that toxin can be produced under any
conditions that permit growth (Stewart, 2003). The Snow Brand Milk Products Co.
outbreak in Japan was suspected to be due to poor cleaning of distribution pipes in
the production facility, leading to the opportunity for S. aureus to grow to high levels
and produce toxin (Asao, 2003).
Listeria m onocytogenes in dairy products
L. monocytogenes has a history of causing large outbreaks from dairy products, with
a 1985 outbreak in the USA from Mexican-style soft cheese affecting 142 people and
causing 48 deaths and an outbreak in Switzerland from Vacherin Mont D'Or cheese
affecting 122 people and causing 34 deaths (Ryser, 1999).
The New Zealand Food Safety Authority (NZFSA) commissioned a series of risk
profiles examining the risk of L. monocytogenes contamination in ice-cream, low
moisture cheese and soft cheeses (see Table 5 for outcomes) while the FDA/USDA
risk assessment on L. monocytogenes examined 11 categories of dairy products
(FDA/USDA, 2003) (see Table 6 for outcomes extrapolated to the Australian
population).
The worldwide incidence rate for Listeria spp. in raw milk is estimated to be around
3–4% (Sutherland et al, 2003), while in Australian raw milk the incidence also
appears low. A NSW Dairy Corporation survey of 600 raw milk samples failed to
detect L. monocytogenes, however, 0.4% of samples were positive for Listeria spp.
(Sutherland & Porritt, 1995).
The organism is eliminated by pasteurisation, therefore the primary concern is postpasteurisation contamination with L. monocytogenes , as it is a common inhabitant
of dairy processing facilities. In dairy factories, the major areas that have been
Page 25 of 189
identified as sources of the organism are drains, floors, conveyors, refrigerated
storage areas and crate wash lines (Sutherland et al, 2003).
Cronobacter sakazakii in infant formula (formerly Enterobacter sakazakii)
C. sakazakii is a rare, but life threatening cause of neonatal meningitis, sepsis, and
necrotising enterocolitis. In general, the reported case-fatality rate varies from 33–
80% among newborns diagnosed with this type of severe infection (Lai, 2001).
Premature infants and those with underlying medical conditions may be at highest
risk for developing a C. sakazakii infection. However, it should be noted that healthy
infants may not always be immune to C. sakazakii infections (Nazarowec-White &
Farber, 1997).
In 2002, the US FDA issued an alert to health care professionals regarding the risk
associated with C. sakazakiiinfections among neonates fed milk-based, powdered
infant formulas (FDA, 2002). There have been several C. sakazakiioutbreaks reported
among infants fed milk-based powdered formula in neonatal intensive care units in
England, Netherlands, Iceland, Belgium, Greece, U.S. and Canada (Biering et al,
1989; Lai, 2001; Van Acker et al, 2001; Himelright et al, 2002). These outbreaks
have involved several deaths and were associated with temperature abuse of
reconstituted powdered infant formula. In addition, there have been cases in
premature babies in New Zealand (NZ Ministry of Health, 2005):
•
1986 – a premature infant contracted C. sakazakii septicaemia. The infant
survived, apparently without serious sequelae
•
1991 – premature twins contracted C. sakazakii meningitis. One twin suffered
serious permanent neurological effects and the other recovered fully
•
2004 – a premature infant contracted C. sakazakii meningitis and died
At the time of writing, there have been no reported cases of neonatal illnesses
associated with C. sakazakiiin infant formula in Australia. However it must be noted
that the organism is not a notifiable disease in Australia.
Powdered infant formula is not a commercially sterile product, unlike liquid formula
which is subjected to sufficient heat to render it commercially sterile. Powdered
infant formula may be subject to contamination by opportunistic pathogens such as
C. sakazakii through improper cleaning of production lines. While the pathogen does
not grow in the powder it can survive for many months (Nazarowec-White & Farber,
1997)
Chemicals
The prevalence of chemical in dairy products is assessed by several surveys
conducted each year in Australia to detect chemical residues. The Australian Milk
Residue Analysis (AMRA) survey, the Australian Total Dietary Survey (ATDS), the
National Antibacterial Residue Minimisation (NARM) program, and other targeted
testing programs provide an indication of the potential for chemical contaminants
ending up in dairy products.
The AMRA survey from 1998 to 2005 showed the following:
•
3,467 milk samples (89,121 analyses) for antimicrobials showed 99.997%
compliance with the maximum residue limit (MRL) for veterinary chemicals
residues in milk (there was one detection of Cloxacillin at a level at the MRL
of 0.01 mg/kg in June 2002 in a bulk milk sample in NSW)
Page 26 of 189
•
33,382 analyses for agricultural chemical residues, including organochlorines,
organophosphates and synthetic pyrethroids, showed no detections
Targeted testing of milk in areas subject to locust plagues has also shown very high
compliance rates for organochlorines, organophosphates and Fipronil (a broad
spectrum insecticide). In 2000–2001, 123 samples were tested in NSW, with no
residues detected (DFSV, 2002).
The NARM program conducts tests for antimicrobials on bobby calves and cull dairy
cows that are presented to abattoirs. Testing on NSW cull dairy cows from 2000 to
2002 showed that 44 from 455 (9.7%) were positive. Of these positive trace results,
eight were shown to be greater than MRL with Neomycin, and Sulphadiazine found in
dairy cull cows, and Oxytetracycline and Sulphadiazine in the export calves. Chemical
residues persist in meat much longer than milk, and this is reflected in recommended
withholding periods. Traceback investigations where residues were detected showed
that causes ranged from not obeying the withholding period, use of the wrong
withholding period (milk rather than meat) and accidental feeding of medicated milk
to calves (NSW Agriculture, 2001 NSW Agriculture, 2002).
The ATDS detected no agricultural chemical residues in milk and milk products
available on retail shelves. Naturally occurring aflatoxins are not considered a high
risk, as a small survey of 40 dairy products by the NSW Food Authority in 2005
detected aflatoxin M1 in trace levels in only one sample, all others were below the
limit of detection.
Risk characterisation
Risk ranking dairy products
The outcomes of the NZFSA risk profiles examining L. monocytogenes and STEC in
dairy products are summarised in Table 5. The FDA/USDA (2003) estimated the risk
per serving and risk per annum of listeriosis for eleven RTE dairy products, based on
the predicted number of illnesses associated with the consumption of these foods.
The risk was calculated for each food on both a ‘per serving’ and ‘per annum’ basis.
Predictions based on the FDA/USDA (2003) risk assessment with a population of 260
million people were extrapolated to the Australian population of approximately 21.6
million (ABS, 2009) by dividing by a factor of twelve. The predicted number of
annual listeriosis cases are presented in Table 6 noting that these estimates are
approximate, as it is acknowledged that there may be differences in the consumption
levels of particular dairy products between American and Australian consumers.
Page 27 of 189
Table 5 – NZFSA risk profile outcomes examining hazards in dairy products
Hazard
Listeria monocytogenes in ice-
cream
(Lake et al, 2003)
Listeria monocytogenes in low
moisture cheese
(Lake et al, 2005a)
Listeria monocytogenes in soft
cheeses
(Lake et al, 2005b)
Shiga-toxin producing
Escherichia coli in raw milk
(Gilbert et al, 2007)
Risk
Found no evidence to link consumption of ice-cream with
cases of L. monocytogenes infection in New Zealand
Contamination with L. monocytogenes is unlikely unless
introduced post-pasteurisation from environmental sources,
added ingredients or further processing such as grating.
Surveys of low moisture cheese suggest that contamination
with L. monocytogenes is infrequent and that growth in
product is unlikely. Even taking into account the high
consumption of low moisture cheese, the available data
indicates that L. monocytogenes in low moisture cheese
does not represent a significant risk to human health
Data on the prevalence of L. monocytogenes indicate that
contamination rates are very low, most likely to occur postpasteurisation. Current risk to the general population is
considered low, although susceptible populations will have
a greater risk
Approximately 10% of notified human cases of STEC
infection (mostly E. coli O157:H7) in New Zealand reported
consumption of raw milk. E. coli O157 has been reported,
albeit rarely, in faecal samples from dairy and beef cattle.
However, there is insufficient data on the prevalence and
numbers of STEC in raw milk to robustly estimate the risk
from consumption of raw milk in New Zealand
Dairy products that are likely to support the growth and survival of pathogens and
are prone to contamination after pasteurisation may be categorised as higher risk
than other dairy products. Alternatively, dairy products that do not support the
growth of pathogens, if correctly formulated, can be classified as low risk. However,
it is also acknowledged that for some pathogens with a low infective dose, survival in
the dairy product may become the issue more than the ability to grow.
FSANZ ranked the degree of risk based on (FSANZ, 2006):
•
intrinsic properties of the product (ie the impact of aw, pH, salt concentration,
and their effect on the growth of contaminating microorganisms)
•
extent to which food is exposed to factory environment or handling after heat
treatment
•
hygiene and control during distribution and retail sale
•
degree of reheating or cooking before consumption (many dairy products are
RTE, so this is rarely a factor)
Page 28 of 189
Table 6 – Risk ranking for dairy products contaminated with Listeria m onocytogenes
Dairy product
Risk ranking
(per serve)
Unpasteurised fluid milk
High fat and other dairy products (eg butter, cream,
other miscellaneous milk products)
Soft unripened cheese, >50% moisture (eg cottage
cheese, cream cheese, ricotta)
Pasteurised fluid milk
Fresh soft cheese
Semi-soft cheese, 39–50% moisture (blue, brick,
monterey, muenster)
Soft ripened cheese, >50% moisture (brie,
camembert, feta)
Ice-cream and other frozen dairy products
Processed cheese (cheese foods, spreads, slices)
Cultured milk products (yoghurt, sour cream,
buttermilk
Hard cheese, <39% moisture (cheddar, Colby,
parmesan)
High
Moderate
Median predicted cases of
listeriosis per serve
(in Australia) 3
7.1 x 10-9
2.7 x 10-9
Risk ranking
(per annum)
Moderate
1.8 x 10-9
Moderate
0.6
Moderate
Low
Low
1.0 x 10-9
1.7 x 10-10
6.5 x 10-12
High
Low
Low
7.5
0
0
Low
5.1 x 10-12
Low
0
Low
Low
Low
4.9 x 10-14
4.2 x 10-14
3.2 x 10-14
Low
Low
Low
0
0
0
Low
4.5 x 10-15
Low
0
Moderate
High
Median predicted annual
number of listeriosis cases
(in Australia) 4
0.25
4.7
adapted from FDA/USDA (2003)
3
4
The risk per serving is inherent to the particular food category, and is therefore assumed to be the same in Australia as that calculated for the USA (FDA/USDA, 2003). This is based on the
assumption that consumption patterns for these foods are identical in Australia and the USA.
The risk per annum has been adapted from USA population data contained in the FDA/USDA (2003) risk assessment of 260 million and extrapolated to Australian population data of
approximately 21.6 million (ABS, 2009) by dividing by a factor of 12
Page 29 of 190
Table 7 provides a relative risk ranking for categories of dairy products (FSANZ,
2006), however the ranking can be quite variable. For example, once a shelf stable
UHT product is opened, it may become contaminated via cross contamination and
when subjected to temperature abuse it could become a high risk food. In contrast,
the low pH and low water activity of extra hard cheese means it is unlikely to support
the growth of any pathogen that contaminates the surface. Dried milk powders and
infant formulae are inherently stable products due to their low water activity,
however pathogens such as Salmonella are able to surive and upon reconstitution
become higher risk, especially if improperly reconstituted and stored.
Table 7 – Risk ranking of dairy products
Risk
ranking
Higher risk
Dairy product
Unpasteurised milk
Soft cheeses
No pathogen reduction step
Mild pH, long shelf life allowing
growth of Listeria monocytogenes
(Bemrah et al, 1998)
Mild pH, fermentable carbohydrate,
long shelf-life
Dependent on variety – some have
low acid, high moisture
Dependent on variety – some have
low acid, high moisture, added
ingredients
Absence of salt, high moisture
content
Absence of salt, high moisture
content
Storage temperature only hurdle to
control post-pasteurisation
contamination
Stored frozen, but soft serve may
allow growth of Listeria
Dairy desserts
Fresh cheese
Dairy dips
Intermediate
risk
Unsalted butter
Low fat spreads
Pasteurised milk
Ice-cream
monocytogenes
Low risk
Yoghurt
Salted butter
Hard cheese
Extra hard cheeses
UHT milk
Dried milk powder
Low pH does not allow growth of
pathogens
High salt concentration
Low water activity, low pH
Low water activity, low pH
Commercially sterile
Low water activity, however prone to
contamination
Consumption of raw milk
The consumption of unpasteurised milk appears to represent a significant risk on a
per serving basis, with the FDA/USDA risk assessment categorising unpasteurised
milk as high risk for listeriosis (FDA/USDA, 2003), and the majority of foodborne
illness attributed to dairy products worldwide due to the consumption of
unpasteurised milk and dairy products made from unpasteurised milk. However, the
predicted number of annual illnesses in the FDA/USDA risk assessment is very low
because of the low levels of consumption of raw milk. From FSANZ consumption
Page 30 of 189
data, it is estimated that the consumption of raw milk as less than 1% of overall milk
consumption (FSANZ, 2006), while the FDA/USDA risk assessment estimated
consumption to be less than 0.5% (FDA/USDA, 2003).
PIRSA commissioned a food safety risk profile on primary production in South
Australia, including milk and dairy products. This report highlighted consumption of
raw milk as a high risk activity and predicted much higher rates of foodborne illness.
It was predicted the risk of illness from all foodborne pathogens associated with raw
milk to be in the order of 36 illnesses per annum among the 1000 consumers,
compared with one illness in 20 years for pasteurised milk (Sumner, 2002).
Control measures
FSANZ found that the factors having the most significant impact on the safety of
processed Australian dairy products are (FSANZ, 2006):
•
the quality of raw materials
•
correct formulation
•
effective processing
•
the prevention of recontamination of product
•
maintenance of temperature control through the dairy supply chain
While pathogenic microorganisms may contaminate raw milk supplies and
pasteurisation is a very effective Critical Control Point (CCP) in eliminating
pathogens, good manufacturing practices must also be employed to ensure that
post-pasteurisation contamination does not occur.
Presence of pathogens in milk
The effectiveness of pasteurisation is dependent upon the microbiological status of
the incoming raw milk. Control measures at the primary production level involve
minimising the likelihood of microbiological hazards contaminating the raw milk. This
is achieved through the implementation of a food safety program incorporating good
agricultural practices (GAP). These measures are effective in reducing the microbial
load of milk being sent for processing.
However, should microbial contamination of raw milk occur, it is critical that milk is
stored at a temperature that minimises the opportunity for the bacteria to multiply.
Temperature abuse of the milk may allow growth of pathogenic bacteria to the
extent where the pasteurisation process may not eliminate all pathogenic bacteria
and/or toxins.
Chemical hazards
Milk from multiple farms may be batched together, either within a milk tanker, or
within a silo at a processing facility, therefore the potential exists for chemically
tainted milk from a single farm to contaminate a large volume of milk within a tanker
and silo at the processing factory. However, the implementation of on-farm food
safety programs has minimised the presence of chemicals in milk.
In addition to these testing programs, processing factories receiving milk from farms
test incoming batches of milk for the presence of chemical hazards, such as
antibiotics which can adversely affect starter cultures during cheese production.
Page 31 of 189
Correct formulation
Ingredients used in the manufacture of dairy products that are added post
pasteurisation must be of a high microbiological standard. Many non-dairy
ingredients added to ice-cream mix after heat treatment include fruits (canned,
fresh, or frozen and usually in concentrated sugar syrups), nuts, chocolate, pieces of
toffee and biscuit, colours and flavours. These ingredients and those added to other
dairy products such as yoghurt, dairy desserts, dairy dips and cheese may introduce
pathogens into the product (ICMSF, 1998). This is readily illustrated by a botulism
outbreak involving a yoghurt product in the UK. In this outbreak it was not the
yoghurt itself but hazelnut purée added to the yoghurt that was the source of the
intoxication. The hazelnut purée was under processed, had a pH (between 5.0 and
5.5) and a high aw conducive to the growth of the pathogen. Previous batches were
sweetened with sugar but the producer had recently switched to aspartame. The
subsequent rise in aw was not compensated for by additional processing changes. A
total of 27 people were affected and one died (Critchley et al, 1989).
This addition of ingredients added after pasteurisation was identified as a high risk
factor by Jansson et al (1999) who recommended that dairy products with these
additions (eg ice-cream and cheeses) be moved into the high risk category and the
finished product be subject to additional end product microbiological analysis.
The microbial quality of dry-blended ingredients into infant formula was identified as
a significant source of contamination by FSANZ, as there is no heat treatment to
destroy bacteria in the final product (FSANZ, 2006).
Effective processing (pasteurisation and equivalence)
Dairy processing facilities primarily use High Temperature Short Time (HTST)
pasteurisation (minimum 72°C for 15 seconds) or batch pasteurisation (minimum
65°C for 30 minutes) to eliminate the pathogens of concern in milk. The minimum
times and temperatures for pasteurisation are stated in Standard 4.2.4 – Primary
Production and Processing Standard for Dairy Products of the Food Standards Code.
However, most factories actually heat the milk to higher temperatures and hold it for
a longer time period as an in-built safety margin.
Juffs & Deeth (2007) undertook an extensive evaluation of the effectiveness of
pasteurisation in reducing pathogens in milk and milk products. They concluded that
Australian consumers can be assured that pasteurisation does destroy the pathogens
of concern in milk and dairy products with a reasonable margin of safety. They also
observed that:
•
literature data indicate that the most significant milk-borne pathogens are
destroyed by pasteurisation with a reasonable margin of safety
•
the pasteurisation times and temperatures used by Australian processors
meets the minimum requirements prescribed in the Food Standards Code,
and in many cases products are heated to a temperature and/or a time often
well in excess of the prescribed minimums
•
lack of epidemiological data indicating that pasteurised milk products have
been implicated in foodborne illness outbreaks in Australia in recent years, in
contrast outbreaks have been associated with consumption of raw milk, in
Australia and overseas
Page 32 of 189
•
in most cases, milk and dairy products are consumed as RTE foods and will
readily support the growth and survival of any contaminating microorganisms.
In the past, the dairy industry has been subjected to a high level of food
safety regulation, ensuring high levels of hygiene and sanitation are
maintained
Pasteurisation destroys many pathogens with a reasonable margin of safety. It will
not destroy C. botulinum spores, heat resistant tnerotoxins, some streptococci and
destruction of some pathogens are debated an uncertain (Juffs & Deeth, 2007). The
pasteurisation process eliminates all pathogenic bacteria likely to be present in raw
milk, with the exception of the spore forming bacteria B. cereus and C. perfringens
and heat resistant toxins. However, neither of these organisms has been identified in
incidents of foodborne illness from dairy products. It is improbable that
C. perfringens can germinate and multiply under the normal conditions of milk
storage, while spoilage bacteria will outgrow B. cereus at refrigeration temperatures.
Processes that are equivalent to pasteurisation are permitted under the Food
Standards Code, including thermisation of milk for cheesemaking when combined
with processing steps that achieve the regulatory food safety criteria.
The prevention of recontamination of product
Post-pasteurisation contamination can pose a major problem where good
manufacturing practices are not employed (Zottola & Smith, 1991). Pathogenic
microorganisms can be introduced into a dairy processing environment with raw
milk. Once these organisms gain access to the processing plant, the presence of
nutrients and moisture can allow not only for survival, but multiplication of these
organisms. The application of food safety programs including elements of Good
manufacturing practice (GMP) and Good hygienic practice (GHP) are critical to limit
the potential for pathogens to contaminate dairy products after pasteurisation.
The primary organisms of concern are L. monocytogenes for most dairy products and
Salmonella in dried milk products. A large number of dairy products have been
recalled due to contamination with L. monocytogenes, with nine recalls between
2004 and 2008 (Table 61 in Appendix 2).
In 1999, the state dairy regulatory authorities introduced two manuals for the control
of post-pasteurisation contamination with Listeria (ADASC, 1999a) and Salmonella
(ADASC, 1999b). These manuals highlight steps to control entry of these organisms
into dairy processing areas, as well as recommend frequencies for finished product
and environmental testing, and clearance programs if the organisms are detected.
Maintenance of temperature control through the dairy supply chain
The intrinsic nature of many dairy products means they will support the growth and
survival of pathogenic bacteria that may contaminate the product. This categorises
these products as ‘potentially hazardous foods’ under the definition in Standard 3.2.2
– Food Safety Practices and General Requirements of the Food Standards Code. The
exception to this are products such as yoghurt, hard cheeses (low pH) and frozen
ice-cream (soft serve ice cream mix may allow growth of L. monocytogenes). As
potentially hazardous foods, maintenance of temperature control through the dairy
supply chain is critical to ensure these foods remain safe and suitable.
Page 33 of 189
Conclusion
The FSANZ risk profile concluded that (FSANZ, 2006):
•
a wide range of microbiological hazards may be associated with raw milk and
dairy products, but these do not represent a significant problem under current
management practices which:
o
control animal health
o
ensure adherence to good milking practices
o
require effective heat treatment (eg pasteurisation) and
o
have controls to prevent post-pasteurisation contamination in the dairy
processing environment
•
current risk management measures ensure that pathogenic microorganisms are
unlikely to be present in high numbers in raw milk
•
pasteurisation (or validated equivalent treatments) provides the kill step to
effectively eliminate all but the spore-forming bacteria and heat resistant toxins
•
there are extensive regulatory and non-regulatory measures in place along the
dairy industry primary production chain resulting in minimal public health and
safety concerns regarding the use or presence of chemical in dairy products
•
extensive monitoring of chemical residues in milk over many years has
demonstrated a high level of compliance with the regulations
•
Australian dairy products have an excellent reputation for food safety, and this is
supported by the lack of evidence attributing foodborne illness to dairy products
•
continuation of the current management practices, particularly monitoring
programs for chemicals along the primary production chain, will ensure that the
dairy industry continues to maintain a high standard of public health and safety
The NSW Food Authority and its predecessor organisations have taken a proactive
role in implementing HACCP-based food safety programs along the dairy supply
chain, a position that may well have contributed to the excellent safety record of
dairy products in NSW. This, when combined with improvements in primary
production practices that effectively manage animal health, adherence to good
milking practices, and improvements in the hygiene of milking equipment and
buildings, has been important in reducing the microbial load in raw milk entering
NSW dairy processing facilities. The adoption of industry codes of practice and the
extensive implementation of food safety programs in the dairy industry has helped to
underpin these regulatory control measures.
Page 34 of 189
References – Milk and dairy products
ABS [Australian Bureau of Statistics] (1995). National Nutrition Survey: Foods Eaten,
Australia, 1995. Australian Bureau of Statistics report. ABS Cat no 4804.0. Retrieved 13
January 2009, from
http://www.ausstats.abs.gov.au/ausstats/subscriber.nsf/0/CA25687100069892CA256888001C
D460/$File/48040_1995.pdf
ABS [Australian Bureau of Statistics] (2009). Population clock. Retrieved 20 February 2009,
from
http://www.abs.gov.au/AUSSTATS/[email protected]/Web+Pages/Population+Clock?opendocument?
utm_id=PC
ADASC [Australian Dairy Authorities’ Standards Committee] (1999a). Australian Manual for
Control of Listeria in the Dairy Industry. Australian Dairy Authorities’ Standards Committee
Manual.
ADASC [Australian Dairy Authorities’ Standards Committee] (1999b). Australian Manual for
control of Salmonella in the Dairy industry. Australian Dairy Authorities’ Standards Committee
Manual.
AgriQuality New Zealand Ltd. (2002). Risk Assessment of Sheep and Goat Milk for SafeFood
(Production) NSW 4.0.
Asao, T., Kumeda, Y., Kawai, T., Shibata, T., Oda, H., Haruki, K., Nakazawa, H. and Kozaki,
S. (2003). An extensive outbreak of staphylococci food poisoning due to low-fat milk in
Japan: estimation of enterotoxin A in the incriminated milk and powdered skim milk.
Epidemiology and Infection 130:33-40.
Barton, M. & Robins-Brown, R.M. (2003). Yersinia enterocolitica In Hocking, A.D. (Ed.).
Foodborne Microorganisms of Public Health Significance (pp. 577-596). Australian Institute of
Food Science and Technology, Waterloo.
Biering, G., Karlsson, S., Clark, N.C., Jónsdóttir, K.E., Lúdvígsson, P. & Steingrímsson, O.
(1989). Three cases of neonatal meningitis caused by Enterobacter sakazakii in powdered
milk. Journal of Clinical Microbiology 27(9), 2054-2056.
Bemrah, N., Sanaa, M., Cassin, M.H., Griffiths, M.W. & Cerf, O. (1998). Quantitative risk
assessment of human listeriosis from consumption of soft cheese made from raw milk.
Preventative Veterinary Medicine 37, 129-145.
Boor, K.J. (1997). Pathogenic microorganisms of concern to the dairy industry. Dairy, Food
and Environmental Sanitation 17, 714-717.
Butt, H.L., Gordon, D.L., Lee-archer, T., Moritz, A. & Merrell, H.W. (1991). Relationship
between clinical and milk isolates of Yersinia enterocolitica. Pathology. 23:153-157.
Christiansson, A., Bertilsson, J. & Svensson, B. (1999). Bacillus cereus spores in raw milk:
factors affecting the contamination of milk during the grazing period. Journal of Dairy Science
82, 305-314.
Critchley, E.M.R., Hayes, P.J. &. Isaacs, P.E.T. (1989). Outbreak of botulism in Northwest
England and Wales. Lancet ii, 8667.
Dairy Australia (2007). Australian Dairy Industry in Focus 2007. Dairy Australia Report.
Southbank, Victoria.
Desmarchelier, P.M. (1998). Enterohaemorrhagic Escherichia coli in Dairy Cattle and Raw
Milk. Dairy Research and Development Corporation Report.
DFSV [Dairy Food Safety Victoria] (2002). Report on the Australian Milk Residue Analysis
Survey 1 July 2000 – 30 June 2001 Results. Australian Dairy Authorities’ Standards Report
prepared by Dairy Food Safety Victoria.
Page 35 of 189
FDA [Food and Drug Administration, US] (2002). Health Professionals Letter on Enterobacter
sakazakii Infections Associated With Use of Powdered (Dry) Infant Formulas in Neonatal
Intensive Care Units. Retrieved 15 January 2009, from http://www.cfsan.fda.gov/~dms/infltr3.html
FDA/USDA [Food and Drug Administration/ United States Department of Agriculture] (2003).
Quantitative assessment of relative risk to public health from foodborne Listeria
monocytogenes among selected categories of ready-to-eat foods. Retrieved 30 October 2008,
from http://www.foodsafety.gov/~dms/lmr2-toc.html.
Forsyth, J.R.L., Bennett, N.M., Hogben, S., Hutchinson, E.N.S., Rouch, G., Tan, A. and Taplin,
J. (2003). The year of the Salmonella Seekers – 1977. Australian and New Zealand Journal of
Public Health. 27:385-389.
FSANZ [Food Standards Australia New Zealand] (2002). Final Assessment Report Proposal
P263. Safety Assessment of raw milk very hard cooked-curd cheeses. Food Standards
Australia New Zealand Report.
FSANZ [Food Standards Australia New Zealand] (2006). A Risk Profile of Dairy products in
Australia. Food Standards Australia New Zealand Report.
Gilbert, S, Lake, R. Hudson, A., & Cressey, P. (2007). Risk Profile: Shiga-toxin producing
Escherichia coli. Institute of Environmental Science and Research Limited report prepared for
the New Zealand Food Safety Authority. Retrieved 13 January 2009, from
http://www.nzfsa.govt.nz/science/risk-profiles/FW0604_STEC_in_raw_milk_July_07.pdf
Himelright, I., Harris, E., Lorch, V. & Anderson, M. (2002) Enterobacter sakazakii infections
associated with the use of powdered infant formula – Tennessee, 2001. Journal of the
American Medical Association 287, 2204–2205.
Hutchinson, D.M., Bolton, F.J., Hinchcliff, P.M., Dawkins, H.C., Horsely, S.D., Jessop, E.G.,
Robertshaw, P.A. & Counter, D.E. (1985). Evidence of udder excretion of Campylobacter
jejuni as the cause of milk-borne campylobacter outbreak. Journal of Hygiene 94, 205-215.
ICMSF [International Commission on Microbiological Specifications for Foods] (1998).
Microorganisms in Foods 6. Microbial ecology of food commodities. Blackie Academic and
Professional, London.
Jansson, E., Moir, C. & Richardson, K. (1999). Final Report Review of Food Safety Systems
developed by the NSW Dairy Corporation. Food Science Australia Report.
Johnson, E.A., Nelson, J.H., & Johnson, M. (1990). Microbiological safety of cheese made
from heat-treated milk, Part II. Microbiology. Journal of Food Protection, 53, 519-540.
Juffs, H. & Deeth, H. (2007). Scientific evaluation of pasteurisation for pathogen reduction in
milk and milk products. Report prepared for Food Standards Australia New Zealand,
Canberra.
Lai, K.K. (2001) Enterobacter sakazakii infections among neonates, infants, children, and
adults: case reports and a review of the literature. Medicine 80, 113–122.
Lake, R. Hudson, A. & Cressey, P. (2003). Risk Profile: Listeria monocytogenes in ice-cream.
Institute of Environmental Science and Research Limited report prepared for the New Zealand
Food Safety Authority. Retrieved 13 January 2009, from
http://www.nzfsa.govt.nz/science/risk-profiles/lmono-in-ice-cream.pdf
Lake, R. Hudson, A., Cressey, P. & Gilbert, S. (2005a). Risk Profile: Listeria monocytogenes in
low moisture cheeses. Institute of Environmental Science and Research Limited report
prepared for the New Zealand Food Safety Authority. Retrieved 13 January 2009, from
http://www.nzfsa.govt.nz/science/riskprofiles/FW0440_L_mono_in_low_moisture_cheese_Final_Mar_2007.pdf
Page 36 of 189
Lake, R. Hudson, A., Cressey, P. & Gilbert, S. (2005b). Risk Profile: Listeria monocytogenes in
soft cheeses. Institute of Environmental Science and Research Limited report prepared for the
New Zealand Food Safety Authority. Retrieved 13 January 2009, from
Lin, S., Schraft, H., Odumeru, J. A. & Griffiths, M. A. (1998). Identification of contamination
sources of Bacillus cereus in pasteurized milk. International Journal of Food Microbiology 43,
159-171.
Martin, W.T., Patton, C.M., Morris, G.K., Potter, M.E. & Puhr, N.D. (1983). Selective
enrichment broth medium for isolation of Campylobacter jejuni. Journal of Clinical
Microbiology 17, 853-5.
Miles, D. (2004). Risk assessment of the NSW Dairy Industry. Report for the NSW Food
Authority, Sydney (unpublished).
Merrilees, C. R. (1943). Report on typhoid fever in the City of Moorabbin, 1943. Commission
of Public Health, Victoria.
Nazarowec-White, M. & Farber, J.M. (1997). Enterobacter sakazakii – a review. International
Journal of Food Microbiology 34(2), 103-113
Notermans, S., Dufrenne, J., Teunis, P., Beumer, R., te Giffel, M. & Peeters Weem, P. (1997).
A risk assessment study of Bacillus cereus present in pasteurised milk. Food Microbiology
14(2), 143-151.
NSW Agriculture (2001) National Antibacterial Residue Minimisation Program 2000 / 2001
Annual Report. NSW Agriculture Report
NSW Agriculture (2002). National Antibacterial Residue Minimisation Program 2001 / 2002
Annual Report. NSW Agriculture Report.
NZ Ministry of Health (2005). Inquiry into Actions of Sector Agencies in Relation to
Contamination of Infant Formula with Enterobacter Sakazakii. Retrieved 17 February 2009,
from http://www.moh.govt.nz/moh.nsf/pagesmh/4020?Open
OzFoodNet Working Group (2007). OzFoodNet quarterly report, 1 January to 31 March 2007.
Communicable Diseases Intelligence 31(2), 234–239.
Ryser, E.T. (1999). Foodborne listeriosis. In E.T. Ryser & E.H. Marth (Eds.) Listeria, Listeriosis
and Food Safety (p 299-358) Marcel Dekker, New York.
Stewart, C. (2003). Staphylococcus aureus and staphylococcal enterotoxins. In Hocking, A.D.
(Ed.) Foodborne Microorganisms of Public Health Significance (pp. 359-379). Australian
Institute of Food Science and Technology, Waterloo.
Sumner, J. (2002). Food Safety Risk Profile for Primary Industries in South Australia (Final
Report). Department of Primary Resources SA, Adelaide. Retrieved 30 September 2008, from
http://www.pir.sa.gov.au/__data/assets/pdf_file/0003/25068/SA_PI_Risk_profile.pdf
Sutherland, P. & Porritt, R. (1995). Dissemination and ecology of Listeria monocytogenes in
Australian dairy factory environments. In ISOPOL XII (Twelfth International Symposium on
the Problems of Listeriosis). Perth, Australia.
Sutherland, P.S., Miles, D.W. & Laboyrie, D.S. (2003). Listeria monocytogenes. In Hocking,
A.D. (Ed.). Foodborne Microorganisms of Public Health Significance (pp. 381–443). Australian
Szabo, E. A. & Gibson, A. M. (2003). Clostridium botulinum. In Hocking, A.D. (Ed.) Foodborne
Microorganisms of Public Health Significance (pp. 505-542). Australian Institute of Food
Science and Technology, Waterloo.
Page 37 of 189
Todd, E. & Harwig, J. (1996) Microbial risk analysis of food in Canada. Journal of Food
Protection (Suppl), 10 – 18
Van Acker, J., de Smet, F., Muyldermans, G., Bougatef, A., Naessens, A. & Lauwers, S. (2001)
Outbreak of Necrotizing Enterocolitis Associated with Enterobacter sakazakii in Powdered Milk
Formula. Journal of Clinical Microbiology, 39(1), 293-297.
Wallace, R.B. (2003). Campylobacter. In Hocking, A.D. (Ed.). Foodborne Microorganisms of
Public Health Significance (pp. 311-331). Australian Institute of Food Science and
Technology, Waterloo.
Zottola, E.A. & Smith, L.B. (1991). Pathogens in cheese. Food Microbiology, 8, 171-182.
Page 38 of 189
Meat food safety scheme
The meat food safety scheme under the Food Regulation 2004 regulates food safety
practices across broad sections of the meat industry, from harvesting of game meat
in the field, through to primary processing at the abattoir and further processing into
ready-to-eat (RTE) meat products. In order to effectively assess the risks, and
consider the different production systems and inherent hazards associated with
different sectors of the meat industry, the following definitions have been used to
categorise the data:
Meat
the dressed carcase and carcase parts of an animal (bovine,
bubaline, camelidae, caprine, cervidae, ovine, porcine and soliped
species)
Poultry meat
the edible part of any poultry (fowl, duck, geese, turkeys,
pigeons, pheasants, quails, guinea fowls and other avian species)
intended for human consumption. For the purposes of this report,
this also includes processed poultry meat
Game meat
the edible part of any wild game animal (any vertebrate animal of
a species that is not farmed, but is killed in the field and can be
legally harvested, excluding fish)
Processed meat
meat that is further processed (such as curing, heat treated,
dried, canned, fermented, rendered) to form a meat product with
different characteristics and flavours
Meat
In Australia, the most comprehensive work has been funded by the meat industry
itself, through Meat and Livestock Australia (MLA), who commissioned a risk profile
of the red meat industry to identify (MLA, 2003a):
•
public health hazards that enter any point of the food chain for red meat
products produced in Australia and rank them in terms of risks to the
consumer
•
hazard:product combinations in which further risk analysis might be
performed
From a regulatory viewpoint, FSANZ will be undertaking a scientific assessment of
the hazards that occur for meat, due to be completed in mid 2009. This work will be
used to underpin broadening of the scope of Standard 4.2.3 – Primary Production
and Processing Standard for Meat of the Food Standards Code to include
requirements for primary production. The standard currently only contains
requirements for producers of RTE meat products.
Beef and sheepmeat
The animal gut is a primary reservoir for a significant number of pathogens and, as
such, may be associated with livestock (Table 8). Bacterial pathogens such as
Salmonella serovars and pathogenic E. coli can persist for extended periods of time
in the farm environment, where they may contaminate feed, water, pasture, farm
equipment through to individual animals or entire herds. It is well established that
cattle are a major reservoir for pathogenic organisms such as Clostridium
Page 39 of 189
perfringens, Campylobacter jejuni, pathogenic Escherichia coli and Salmonella
serovars in their gut including the rumen, caecum, colon and rectum (McEvoy et al,
2004). From these locations, pathogens are frequently transferred to the exterior,
such as the hide and hooves and to the surrounding environment. In addition,
sheep, cattle and pigs grazing on contaminated pastures can become infected with
the encysted form of the parasite Toxoplasma gondii.
Because livestock may serve as a reservoir for pathogens, it is not surprising that a
number of these animals will carry pathogens into the abattoir environment. While
the muscle tissue of healthy live animals is essentially sterile at the time of slaughter,
the external surfaces of carcases may become contaminated during de-hiding and
dressing, and if the intestinal tract is punctured and the gut contents escape. This
can also lead to direct or indirect contamination of equipment and workers during
dressing and processing, which may further contribute to carcase cross
contamination.
Internationally, the European Food Safety Authority (EFSA) has undertaken a risk
assessment on Salmonella in meat (EFSA, 2008), while risk assessment work in the
USA has tended to concentrate on specific hazards such as E. coli O157:H7 in
hamburgers (Cassin et al, 1998) and in tenderised meat (FSIS, 2002). Although a
hazard of concern in the USA, the prevalence of E. coli O157:H7 on Australian beef
and sheep carcases appears to be very low (MLA, 2000; 2005). This organism does
not appear to be a significant source of foodborne illness in Australia, with only two
cases reported in a chiold care centre in Victoria in 1996 (See Table 69).
In addition to the traditional bacterial pathogens, worldwide attention became
acutely focussed on the possible acquisition of variant Creutzfeldt-Jakob Disease
(CJD) from Bovine Spongiform Encephalopathy (BSE) infected animals. However,
under the assessment of Geographical BSE Risk (GBR), Australian livestock are
considered ‘highly unlikely’ as having BSE (EFSA, 2007). The potential risk factors for
BSE have been addressed through the implementation of appropriate control
measures within Australia.Therefore, BSE will not be further considered in this risk
assessment.
Pigmeat
Pigs are often associated with the carriage of Yersinia enterocolitica, appearing to be
the primary source of Yersinia infections in humans caused by bioserotype 4,O:3
(Barton & Robins-Browne, 2003). The pork tapeworm Taenia solium (larval stage
Cysticercus cellulosae) and the nematode worm Trichinella spiralis are often
associated with pork overseas. However these organisms are not present in
Australian pigs (DAFF, 2004) and, therefore, are not further considered in this risk
assessment.
Page 40 of 189
Table 8 – Microbiological hazards in livestock and poultry
Livestock
Pathogenic bacteria
pathogenic Escherichia coli
Salmonella serovars
Brucella
Coxiella burnetii
Bacillus anthracis
Clostridium spp.
Mycobacterium bovis
Streptococcus spp.
Poultry
Salmonella serovars
Parasites
Cysticercus bovis
Cysticercus ovis
Onchocerca spp.
Taenia saginata
Toxoplasma gondii
Prions
Bovine Spongiform Encephalopathy (BSE)
adapted from Sumner (2002); FSANZ (2005)
The rate of carriage of the pathogenic organisms in the gut by livestock may be
affected by factors such as animal handling, husbandry techniques and other onfarm practices that can affect animal health. Practices such as co-mingling of
animals, intensive rearing methods and stress (such as starvation and transport)
have been shown to increase the shedding and transmission of pathogens in
animals.
Chemical hazards in the red meat industry were assessed as part of the risk profile
conducted by the MLA. This work found that the current system for registering and
monitoring the use of chemicals in the meat industry to be well managed. The
incidence and levels of residue contamination reported by the National Residue
Survey (NRS) and the Australian Total Diet Survey (ATDS) are very low. In instances
where chemical residues have been detected in meat, the levels found have been too
low to be considered a public health risk
The MLA risk profile could find no data on physical hazards for the red meat industry.
Poultry meat
Internationally, a huge amount of resources have been employed to undertake risk
assessment work on poultry. This work has concentrated on the pathogens
considered to be most significant, namely Salmonella (FAO/WHO, 2001; WHO/FAO,
2002) and Campylobacter (FAO/WHO, 2003).
In Australia FSANZ has undertaken a comprehensive scientific assessment of the
poultry meat industry to underpin the development of Standard 4.2.2 – Primary
Production and Processing Standard for poultry meat (FSANZ, 2005). This work
considered:
Page 41 of 189
•
the extent of food safety risk associated with the consumption of poultry
meat and poultry meat products in Australia
•
the factors along the poultry meat supply chain that have the greatest impact
on public health and safety
A range of microbiological hazards may be introduced to poultry meat during the
primary production stages. These include bacterial pathogens that may contaminate
breeding stock, feed, water and the environment. The FSANZ scientific assessment
considered Salmonella serovars, Campylobacter spp., pathogenic E. coli, S. aureus,
C. perfringens and L. monocytogenes as potential hazards in poultry meat.
Poultry are exposed to Salmonella via sources such as feed or through environmental
contamination. Once infected, a bird will excrete large numbers of salmonellae in its
faeces which can lead to rapid spread throughout the flock. Salmonella positive birds
at the time of slaughter have high numbers of organisms in their intestines as well as
on external surfaces. Slaughtering and processing operations have the potential to
contaminate the poultry carcase with faecal material and to facilitate cross
contamination between pathogen-positive birds and pathogen-negative birds, leading
to increased prevalence of Salmonella in finished products. This may occur at various
stages of processing including unloading of birds, scalding, plucking, evisceration,
washing and chilling. Care must be taken during evisceration to ensure the viscera is
not damaged or ruptured as this can lead to significant contamination of the carcase.
The means by which broiler chickens become exposed to contamination with
Campylobacter during primary production is multi-factorial (FSANZ, 2005). Numerous
factors in combination result in the introduction and spread of the organism within a
flock. Campylobacter will colonise individual birds at two or three weeks of age, and
usually within a week virtually all birds in the flock will become infected. Horizontal
transmission is mainly through contaminated water, litter, insects, rodents, and wild
birds and by farm workers via their boots (Wallace, 2003). The implication of this is
that, unless a flock is Campylobacter free, virtually all birds in a positive flock will be
carrying Campylobacter in their intestinal tract at the time of slaughter in high
numbers.
The FSANZ risk assessment concluded that although poultry meat may occasionally
be contaminated with other pathogens, Salmonella and Campylobacter are the
primary pathogens of concern and risk management strategies should be targeted to
controlling these organisms (FSANZ, 2005). These two organisms are the leading
causes of foodborne illness in Australia each year and are frequently isolated from
raw poultry meat. They become associated with poultry during primary production
and their prevalence and/or levels may be amplified during primary processing and
further handling through to consumption.
The FSANZ risk assessment found that the risk associated with the other pathogens
was primarily a concern during the production of processed poultry meat products
and temperature abuse of RTE poultry products (FSANZ, 2005). The hazards
associated with further processing of poultry meat are outlined in the sections on
processed meat.
Game meat
The main species harvested as game meat are kangaroo and pigs. Very little data
exists for hazards in game meat, however kangaroo meat has been studied in some
depth as the industry attempts to market the product to increase consumption rates
Page 42 of 189
in the general population. Kangaroo meat is anecdotally stated as being a particular
risk for toxoplasmosis and salmonellosis, however it appears as if there is little
evidence to substantiate that kangaroo meat has Salmonella rates higher than other
animals, and there is no known case of toxoplasmosis being transmitted by eating
kangaroo meat in Australia.
There is a risk of physical hazards in game meat, however strict guidelines exist for
the harvesting of product. The animal must be head shot, not only to ensure a quick
kill but also to prevent damage to the skin, carcase and internal organs which are
required for inspection purposes, and to limit the potential for shot to contaminate
the meat.
Processed meats
The risk posed by processed meats, such as manufactured and fermented meats was
highlighted in the National Risk Validation Project (Food Science Australia & Minter
Ellison Consulting, 2002), with these products classified as a high risk and earmarked
for the introduction of food safety programs. The pathogens of significance for
processed meats were identified as L. monocytogenes, Salmonella and pathogenic
E. coli, as these had been previous causes of foodborne illness outbreaks in
Australia.
The primary sources of contamination for processed meats includes the
contaminants associated with raw meat (eg pathogenic E. coli, Clostridium spp.,
Salmonella serovars), other ingredients such as spices (eg Salmonella serovars) and
from the processing environment (eg L. monocytogenes), especially for products that
are subject to further processing such as slicing (MLA, 2003a).
Control of these organisms is normally through appropriate processing with Critical
Control Points (CCPs) to inactivate these pathogens, such as cooking, fermentation
with starter cultures and curing (MLA, 2003b). However, this does not eliminate any
contamination that occurs post-processing, and as such L. monocytogenes has been
the cause of many recalls of processed meats (Table 62 in Appendix 2) and
responsible for several very large outbreaks overseas from RTE processed meat
products (Doolittle, 2008).
A potential chemical hazard with processed meat is the inclusion of preservatives
such as sorbate and nitrate salts, particularly for cured products, in exceedance of
limits in the Food Standards Code (MLA, 2003b).
Exposure assessment
Consumption of meat
Daily consumption of meat and meat products was assessed during the National
Nutrition Survey (ABS, 1995), which examined overall consumption of meat,
including poultry and processed meats. The survey showed that approximately three
quarters of the Australian population regularly consume meat and meat products,
with males consuming slightly higher levels than females (Table 9). Consumption of
specific types of meat was estimated in the ABARE report (ABARE, 2007) and by MLA
through production statistics (MLA, 2008a; MLA 2008b).
Page 43 of 189
Beef
Consumption of beef and veal in 2006 was estimated by ABARE at 38.1 kg per
person per year, while MLA estimates beef consumption alone at 35.6 kg beef per
year (MLA, 2008a). Consumption of beef and veal has been steadily decreasing since
the peak consumption period of the late 1970s.
Sheepmeat
Australians are among the highest consumers of lamb in the world, consuming
11.4kg of lamb and 2.7kg of mutton per person every year (MLA, 2008b).
Pigmeat
A considerable amount of the 23.5 kg of pork consumed by each person per year is
eaten as processed product (see consumption of processed meats). Consumption of
fresh pork in 2006 was estimated at 11.1 kg per person (APL, 2008).
Consumption of poultry meat
Annual per capita consumption of poultry meat in 2006 was estimated at 39.5 kg
(ABARE, 2007). Chicken consumption accounts for approximately 95% of all poultry
consumed, with the annual consumption of turkey and duck in Australia estimated at
1.6 kg and 0.5 kg per person respectively (FSANZ, 2005). FSANZ estimated the total
number of poultry servings in Australia annually to be 2,880,000,000, with an
average serving size of 250g.
Consumption of game meat
Very little consumption data specific to game meat is available and, when compared
to the major meat categories, forms a very small part of the average persons diet.
Ampt & Owen (2008) surveyed consumer attitudes towards the consumption of
kangaroo meat and found that 58.5% of respondents had tried the meat, with
14.5% having eaten kangaroo meat at least four times in the past year (classed as
‘medium to high’ consumers). In NSW/ACT there were 549 respondents surveyed,
with 14.2% were classified as medium to high consumers, 19.5% were nonconsumers, 43.9% were one-off or low consumers, and 22.4% objected to eating
kangaroo meat. Men were marginally more likely to consume kangaroo than women.
Ampt & Owen (2008) went on to report that although there had been considerable
changes in the kangaroo industry over the past ten years, with the widespread
availability of kangaroo in domestic supermarkets, the industry still remains reliant on
export markets.
Page 44 of 189
Table 9 – Consumption of meat and meat products in Australia
Sex
Age
Male
Male
Male
Male
Male
Male
Male
Male
Male
Female
Female
Female
Female
Female
Female
Female
Female
Female
2–3
4–7
8 – 11
12 – 15
16 – 18
19 – 24
25 – 44
45 – 64
65+
2–3
4–7
8 – 11
12 – 15
16 – 18
19 – 24
25 – 44
45 – 64
65+
consuming meat, poultry,
game products and
dishes 5
(%)
76.7
72.4
77.0
78.8
80.9
84.1
84.4
87.6
84.7
71.7
73.6
78.3
80.2
74.5
74.0
76.9
77.5
79.7
Median daily intake for
consumers of meat, poultry,
game products and dishes
(g/day)
62.7
84.3
115.6
143.0
196.0
224.0
191.8
168.0
126.5
52.3
77.9
95.3
113.1
131.0
141.4
126.0
114.3
83.0
Table 10 – Consumption of processed meats in Australia
Product category
Processed meats
(hams, whole muscle cooked meats)
Cooked sausages (frankfurters, saveloys)
Pâté and meat paste
Daily serving size (grams per person)
28 – 58
63 – 108
40 – 56
adapted from MLA (2006)
Consumption of processed meats
The MLA (2006) reported consumption data for categories of processed meats. On
any given day between 20 and 50% of the population consume processed meats.
The amounts consumed are shown in Table 10. Consumption of processed pig meat,
as bacon and ham, contributes approximately 14.4 kg per person per year (APL,
2008).
5
Meat, poultry and game meat products and dishes are defined in the National Nutrition Survey (ABS, 1995) as
including the following:
- muscle meat,
- poultry and other feathered game,
- organs meats and offal, products and dishes,
- sausages, frankfurts and saveloys,
- processed meat,
- mixed dishes where beef or veal is the major component,
- mixed dishes where lamb or pork, bacon or ham is the major component,
- mixed dishes where poultry or game is the major component
Page 45 of 189
Foodborne illness outbreaks from meat and meat products
Table 11 summarises the foodborne illness outbreaks attributed to all meat and meat
products, including poultry, game and processed meats. This data also includes
outbreaks where meat was an ingredient in an implicated food (more detailed
information on each outbreak is included in Table 66 in Appendix 3).
Table 11 – Summary of foodborne illness outbreaks attributed to all meat, meat
products and meat included as an ingredient (1995–2008) (including
poultry, game meat and processed meat products)
Hazard
Salmonella serovars
C. perfringens
Campylobacter spp
Toxin
Norovirus
Viral
S. aureus
B. cereus
L. monocytogenes
Pathogenic E. coli
Shigella spp.
Unknown
Total
Australian
outbreaks
(1995–2008)
74
27
14
6
5
5
4
2
1
1
1
63
203
Cases
1829
804
106
520
201
175
51
20
32
173
13
766
4690
Hospitalisations
97
0
2
0
5
0
5
0
0
0
0
5
114
Deaths
2
0
0
0
0
0
0
0
0
1
0
0
3
Meat
The European Food Safety Agency (EFSA, 2008) evaluated the relative contribution
of different meat categories to cases of foodborne salmonellosis infections in humans
and found that poultry was more often implicated than beef, pork and lamb. Adak et
al (2005) used data from foodborne illness outbreaks in England and Wales to
attribute the source of various types of implicated meats. In this study the most
important cause of foodborne illness was chicken (398,420 cases, 141 deaths) while
red meat was also a very significant source (287,485 cases, 164 deaths).
Three major microbiological baseline surveys have been undertaken by MLA of red
meat processed in Australian abattoirs (MLA, 2000; MLA, 2005). These surveys
provide a useful indication of the prevalence and levels of hygiene indicators such as
Total Viable Count (TVC), as well as pathogens such as Escherichia coli O157:H7 and
Salmonella serovars on carcases and in boneless meat (see Table 12). The surveys
have shown an improvement in both the prevalence and levels of microbiological
contamination every 5–6 years that the surveys have been conducted. This has been
attributed to significant improvements in hygiene and sanitation during primary
processing and efficient cooling of carcases.
A baseline survey of NSW abattoirs by the NSW Food Authority (Bass et al, 2008)
found a strong commitment to food safety and that facilities were managing food
safety issues well. Surveys of carcase and meat portion load-out temperatures found
that 96% of product complied with temperature requirements. However, only 38% of
offal samples complied. The microbiological hygiene of beef carcases sampled were
Page 46 of 189
categorised as excellent 6 or good, with TVC counts ranging from 0.48 log cfu/cm2 to
3.95 log cfu/cm2. One quarter of the beef carcases sampled tested positive for
E. coli. This prevalence is higher than that found in the national MLA surveys, but the
levels detected were quite low, with counts ranging from -0.89 log cfu/cm2 to 0.69
log cfu/cm2. Almost all sheep carcases (lamb/hogget/mutton) were rated as excellent
or good for TVC and E. coli respectively. The sheep TVC counts ranged from 0.30 log
cfu/cm2 to 5.47 log cfu/cm2. Just over half (53%) of the sheep carcases tested were
positive for E. coli, counts ranging from -0.48 log cfu/cm2 to 2.24 log cfu/cm2. The
hygiene results for pig carcases showed that 80% were rated as excellent or good
for TVC, and 91% rated as excellent or good for E. coli. The pig TVC counts ranged
from 0.85 log cfu/cm2 to 5.03 log cfu/cm2. The percentage of carcases testing
positive for E. coli was 63%, with counts ranging from -1.10 log cfu/cm2 to 1.30 log
cfu/cm2.
European surveillance schemes have found the proportion of fresh beef positive for
Salmonella serovars to be below 0.6% at slaughter, with higher levels at retail
(8.3%) (EFSA, 2008). Despite worldwide consumption of lamb and mutton, these
products have rarely been associated with salmonellosis in humans.
There has been a two-pronged approach to controlling hazards in the meat industry.
Hazards related to zoonotic diseases have been controlled through the application of
preventative programs, such as the Brucellosis and Tuberculosis eradication
campaign (BTEC), which was aimed at eradicating brucellosis and tuberculosis from
all Australian cattle. As a result, Australia has been free of brucellosis caused by
Brucella abortus since 1989, and bovine tuberculosis-free status was achieved in
1997, which is now assessed through the Tuberculosis Freedom Assurance Program
(TFAP) and National Granuloma Submission Program (NGSP). The second prong has
been the implementation of the Australian Standard for the hygienic production and
transportation of meat and meat products for human consumption (FRSC, 2007c)
and previous versions of this standard.
6
Meat Standards Committee (2002) – Microbiological testing for process control in the meat industry - guidelines
defined the following categories:
- Total Viable Count (TVC)

Excellent (<103 cfu/cm2)

Good (103-104cfu/cm2)

Acceptable (104–105cfu/cm2)

Marginal (105-106cfu/cm2)
- E. coli

Excellent (not detected)

Good (>0-10 cfu/cm2)

Acceptable (10-100cfu/cm2)

Marginal (100-103cfu/cm2).
Page 47 of 189
Table 12 – Prevalence of microbiological hazards in Australian beef and sheep
meat
Beef carcases
Number of samples
TVC (mean log cfu/g)
E. coli (%)
S. aureus (%)
Salmonella (%)
E. coli O157:H7 (%)
Listeria
Campylobacter
Boneless beef
Number of samples
E. coli (%)
S. aureus (%)
Salmonella (%)
E. coli O157:H7 (%)
Boneless sheepmeat
Number of samples
E. coli (%)
S. aureus (%)
Salmonella (%)
E. coli O157:H7 (%)
1993 survey
1998 survey
2004 survey
1043
3.02
19
128/465 (27.5%)
4/1043 (0.38%)
4/1036 (0.38%)
4/190 (2.1%)
2/753 (0.26%)
1268
2.43
11
3.9
0.6
not detected
1155
1.33
4.9
20.1
0
0.1
929
2.77
16.7
n/a
6/921 (0.65%)
0/804 (not detected)
987
3.52
5.1
17.5
0.1
not detected
1082
1.19
1.1
2.6
0.1
0
415
3.47
47.7
n/a
27/415 (6.5%)
1/342 (0.3%)
467
3.29
24.5
38.6
1.3
1.3
560
1.81
4.3
14.1
0.5
0.2
0
adapted from MLA (2000); MLA (2005)
NSW legislation requires that any abattoir processing meat must comply with the
AS4696:2007. As part of compliance with this standard, all abattoirs must have
qualified meat safety inspectors (meat safety officer) to conduct ante-mortem
inspections of livestock prior to slaughter. This is used to identify any stock
suspected of carrying infectious zoonotic diseases, which may then be culled to
prevent spread to healthy stock. Online post-mortem inspection in abattoirs is used
to identify and excise diseased tissues and organs and/or to exclude diseased
carcases from human consumption.
Many studies have been undertaken to assess the influence of different processing
practices in contributing to microbial contamination of carcases. Widders et al (1995)
showed that the level of microbial contamination of meat was influenced by the level
of carcase contamination at boning, and by the boning process itself. If carcases
were heavily contaminated, the contamination of processing surfaces was irrelevant
in determining eventual microbial loads on meat. However, where carcase
contamination was at low to moderate levels, cutting boards were a major source for
microbial dissemination during the boning process. It was shown that improved
sanitation of cutting surfaces in the boning room could result in a significant
reduction in microbial contamination on the surface of meat.
Special control measures have also been implemented to target specific hazards of
concern in pigs. In order to minimise pig carcase contamination with Y. enterocolitica
during slaughter, the tongue and pharynx are removed early in the slaughter process
to reduce the leakage of saliva and contaminated material from the tongue and
tonsils onto the carcase (Barton & Robins-Browne, 2003).
Page 48 of 189
The NRS and Australian Total Diet survey results show that misuse of agricultural
and veterinary chemicals within the meat industry is low, with most analyses
returning either no detectable residues or residues well below established legal limits.
As a result, the Australian dietary exposure to pesticides and contaminants falls well
within acceptable health standards (MLA, 2003a).
Poultry meat
The FSANZ poultry risk assessment summarised OzFoodNet data for foodborne
illness outbreaks in Australia from poultry meat products (FSANZ, 2005). Between
1995 and 2002 they reported 46 outbreaks involving 1170 cases. The data in Table
66 of Appendix 3 includes and updates the outbreaks from the FSANZ report. From
1995–2008, 94 outbreaks were attributed to products containing chicken, affecting
1815 people and 54 requiring hospitalisation. In addition to these outbreaks, another
six outbreaks were observed in institutional settings serving vulnerable persons.
Details on these outbreaks are included in Table 69 of Appendix 3. A case control
study conducted on foodborne illness outbreaks in New Zealand concluded that
consumption of raw and undercooked chicken was the most important source of
human campylobacteriosis (Eberhart–Phillips et al, 1997).
The EFSA (2008) reported prevalence of Salmonella in EU member countries at
slaughter ranging from 5.7% to 21.5%, while prevalence in fresh turkey meat varied
from 0 to 11%, fresh duck meat from 15 to 39% and 10% in fresh geese meat.
Although data is not readily available for contamination rates at slaughter for
Australian birds, a survey of retail chicken in NSW from 2005 to 2006 found 47.7%
of poultry samples contained low levels of Salmonella. However, of the Salmonella
serovars isolated approximately 65% were the serovar S. Sofia, considered of very
low virulence to humans. In addition, 87.8% of poultry samples were found to be
contaminated with Campylobacter (Pointon et al, 2008, summarised in Table 13).
All facilities slaughtering and processing poultry in NSW are required to comply with
AS 4465:2005, the Australian Standard for the construction of premises and hygienic
production of poultry meat for human consumption (FRSC, 2007a). This requires
ante-mortem inspection of poultry presented for slaughter to reject any moribund,
unhealthy or diseased birds and post-mortem inspection to identify and apply a
disposition to any carcase and parts that are not considered wholesome for human
consumption.
In addition to the regulatory requirements, there are various industry codes of
practice and guidelines, such as the National Biosecurity Manual Contract Meat
Chicken Farming (ACMF, 2003) and Model Code of Practice for the Welfare of
Animals – Land Transport of Poultry (PISC, 2006). These codes of practice
concentrate on prevention of animal disease and welfare aspects, with potential
implications for food safety. The extent of compliance with these control measures
varies within the poultry industry, depending on whether it is a legislative
requirement or a voluntary scheme.
Page 49 of 189
Table 13 – Prevalence of microbiological hazards on retail chicken meat in NSW
(2005–06)
Retailer
Product
Butcher
Skin off
Skin on
Supermarket
Specialty
store
Whole
bird
Skin off,
bulk
Skin off,
tray
Skin on,
bulk
Skin on,
tray
Whole
bird
Skin off
Skin on
Whole
bird
TOTAL
Number
positives
/ total
samples
(%)
18/28
(64.3)
29/47
(61.7)
7/9
(77.8)
21/37
(56.8)
39/106
(36.8)
28/50
(56.0)
63/150
(42.0)
11/37
(29.7)
14/28
(50.0)
28/47
(59.6)
4/10
(40.0)
262/549
(47.7)
Salm onella
Mean
concentration
± SD
NonSofia
(%)
-1.31 ± 0.58
7.1
-1.18 ± 0.70
44.7
-1.70 ± 0.95
0.0
-1.41 ± 0.33
13.5
-1.38 ± 0.41
16.0
-1.43 ± 0.47
18.0
-1.48 ± 0.67
9.3
-1.75 ± 0.76
5.4
-1.33 ± 0.58
21.4
-1.38 ± 0.60
21.3
-2.05 ± 0.04
10
-1.42 ± 0.60
15.8
Cam pylobacter
Number
positives
/ total
samples
(%)
27/28
(96.4)
40/47
(85.1)
8/9
(88.9)
35/37
(94.6)
95/106
(89.6)
42/50
(84)
124/150
(82.7)
34/37
(91.9)
25/28
(89.3)
44/47
(93.6)
8/10 (80)
Mean
concentration
± SD
482/549
(87.8)
0.87 ± 0.45
1.14 ± 0.57
1.24 ± 0.64
1.11 ± 1.00
1.06 ± 0.35
0.90 ± 0.27
0.82 ± 0.23
0.66 ± 0.36
0.61 ± 0.53
1.04 ± 0.35
0.90 ± 0.35
0.77 ± 0.37
adapted from Pointon et al (2008)
The high risk factors for poultry becoming contaminated with Salmonella or
Campylobacter were identified in the FSANZ scientific assessment (FSANZ, 2005).
The development of Standard 4.2.2 – Primary Production and Processing Standard
for poultry meat in the Food Standards Code aims to reduce the contamination of
poultry, poultry carcases and poultry meat by pathogenic Salmonella and
Campylobacter through the implementation of control measures on-farm, as well as
maintain existing control measures during processing at abattoirs.
Game meat
NSW legislation requires that harvesting facilities, primary processing and storage
facilities and vehicles comply with AS4464:2007, the Australian Standard for the
hygienic production of wild game meat for human consumption (FRSC, 2007b). This
requires that all carcases are subject to inspection by a qualified meat safety
inspector and temperature control of the carcase is maintained. There is no data to
indicate that game meat has been the subject of any foodborne illness outbreaks or
recalls. There is also no recent data to indicate prevalence of microorganisms on
game meat carcases, although it is assumed that with similar control measures in
place to the broader meat industry, that the prevalence of pathogens may be similar.
Page 50 of 189
The incidence of zoonoses and other public health risks from kangaroo meat was
investigated and summarised by Andrew (1988), quoted in Pople & Grigg (1999).
The work summarised the records of inspections between 1980 and 1987 made of
carcases by AQIS officers at export game meat establishments. Of the 204,052
kangaroo carcases harvested, 196,104 were passed as fit for human consumption
and 7948 were rejected. Of those rejected, 81% were rejected for reasons not
associated with parasites or pathology, mainly poor handling, particularly inadequate
refrigeration. Of the rest, 1452 were rejected because of a nematode parasite,
Pelicitus roemeri, which is harmless to humans but is considered unsuitable for
human consumption.
Processed meat products
Processed meat products have been implicated in several large scale food poisoning
outbreaks, both overseas and within Australia (see Table 14 and Table 66 of
Appendix 3). For the period 1991–2000, the National Risk Validation Project
identified greater than 323 cases of foodborne illness and one death attributed to the
consumption of fermented meats, with a further 97 cases and two deaths attributed
to other manufactured meat products. The pathogens implicated in these outbreaks
were pathogenic E. coli, L. monocytogenes and Salmonella and the total cost of
foodborne illness associated with fermented and manufactured meats was calculated
to $77 million per year (Food Science Australia & Minter Ellison Consulting, 2002)
The most significant outbreak from a processed meat product occurred in 1995 in
South Australia from Garibaldi-brand Mettwurst, with over 150 people ill and the
death of a young child from E. coli O111. Well controlled fermentation and
maturation should achieve a low pH and water activity to eliminate any pathogens
present in the raw meat ingredient. However, uncontrolled fermentation, as was the
case with the Garibaldi product, can lead to survival of pathogens. This outbreak led
to changes to the Food Standards Code and regulations regarding the manufacture
of uncooked comminuted fermented meats.
An outbreak of listeriosis from Conroy’s smallgoods occurred in South Australia in
2005, resulting in three deaths of hospital patients. Listeria was isolated from the
slicing machines in the factory used to slice the deli meats. Details are included in
Table 69 in Appendix 3, as the food was served to vulnerable persons. The cost of
the subsequent recall by Conroy’s was in the order of $2 million. A Canadian
outbreak in 2008 from Maple Leaf Foods Inc. resulted in 20 deaths, and the resultant
recall of more than 220 product lines and settlements from class action lawsuits was
in the order of $27 million (AUS$ 33 million) (Doolittle, 2008).
The manual handling associated with preparing and packaging processed meat
products tend to lend themselves to contamination with L. monocytogenes. Surveys
have shown a significant number of RTE processed meat products are contaminated
with this organism (Table 15). Sliced meats in particular tend to have higher
contamination rates with L. monocytogenes, although actual numbers of organisms
are quite low. The long shelf life associated with these products (~ six weeks) can
allow growth of the organism to occur. Advice provided to susceptible persons, such
as pregnant women, is to avoid consuming pre-packaged sliced meats. Table 62 of
Appendix 2 shows the number of recalls from RTE processed meats from 2004-08,
during which time there have been 33 recalls, mostly due to contamination with
L. monocytogenes.
Page 51 of 189
NSW legislation requires that any facility producing processed meat must comply
with AS4696:2007 the Australia Standard for the hygienic production and
transportation of meat and meat products for human consumption (FRSC, 2007c). In
addition to this, there are industry produced documents such as Guidelines for the
safe manufacture of smallgoods (MLA, 2003b) and Listeria monocytogenes in
smallgoods: Risks and controls (MLA, 2006), which provide information on hygiene
and sanitation and CCPs for controlling hazards.
Table 14 – Foodborne illness outbreaks of listeriosis from processed meats
Year
1987–89
1990
1992
1993
1996
1998–99
1999
1999
1999
2000
2000–01
2002
2005
2008
Country
United Kingdom
WA
France
France
SA
USA
France
USA
France
New Zealand
USA
USA
SA
Canada
Processed meat
Pâté
Pâté
Jellied pork tongue
Pork rillettes, pâté
Diced chicken
Hot dogs and deli meats
Ham rillettes
Pâté
Jellied pork tongue
Corned beef
Turkey franks
Deli meats (poultry)
Corned beef
Deli meats
Cases
366
11
279
39
5
101
>6
11
23
2
>29
>50
5
50
Deaths
94
6
85
11
1
21
2
3
7
>7
11
3
20
adapted from MLA (2006); Doolittle (2008)
Table 15 – Prevalence of Listeria m onocytogenes in processed meats
Product category
Processed meats (hams, whole muscle
cooked meats)
Cooked sausages (Frankfurters, saveloys)
Pâté and meat paste
Contamination rate (%)
4.8
2.8
1.2
adapted from MLA (2006)
Red meat
The MLA risk profile examined the risk of fresh meats consumed in the home and
found that meat consumed as cuts, roasts, chops, steak are low risk (MLA, 2003a).
These products normally receive a cooking step by the end consumer that will
reliably eliminate most pathogenic bacteria. However, the importance of cross
contamination from pathogens in raw and undercooked meat across to RTE foods
was highlighted by Lake et al (2004) as a potential source of infection from Yersinia
in pork (Table 16), and as a potential source for large numbers of Salmonella food
poisoning cases (Table 17). It was predicted that if the cross contamination rate of
Salmonella from raw meat to RTE foods increased from 1% to 10% it would result in
almost an extra 4800 cases, while an increase to a 50% cross contamination rate
would result in more than 26,000 cases of foodborne illness in Australia each year,
where fresh meat was the cause (MLA, 2003a).
Another hazard categorised as high risk by the MLA risk profile was undercooked
sheep meat or liver contaminated with Toxoplasma gondii, particularly when
Page 52 of 189
consumed by pregnant women (MLA, 2003a). This area was identified as a data gap
in work undertaken on the New Zealand meat industry by Lake et al (2002b). While
it was predicted there may be more than 600 cases of illness due to infection
withToxoplasma gondii per annum (200 in pregnant women), further work was
required to fully understand the risk factors involved.
Undercooking of meat and hamburgers is associated with survival of pathogenic
E. coli and the ranking of this pathogen as a medium hazard. However, a study by
the FSIS (2002) in the USA calculated the probability of illness occurring as
extremely low. This work estimated that the probability of E. coli O157:H7 surviving
in a piece of cooked steak was 0.000026% (2.6 of every 10 million servings), given
normal cooking practices. It was shown that even inadequate cooking of meat would
still reduce the numbers of pathogenic E. coli present on the meat, albeit to a lesser
degree than proper cooking. The predicted number of food poisoning cases from
E. coli O157:H7 in cooked steaks was calculated to be one case for every 15.9 million
servings (FSIS, 2002). The risk of illness from pathogenic E. coli in New Zealand
meat was considered low by Lake et al (2002a), as there was no data to link illness
to pathogenic E. coli in that country. The risk from comminuted meat such as
hamburgers is considered greater, as the contamination may be spread throughout
the product, as opposed to just the surface on an intact steak. The MLA risk profile
estimated that if all hamburgers were appropriately cooked, there would be no
illness. However, if 20% of hamburgers were undercooked, there would be six
illnesses per annum in Australia (MLA, 2003a).
The NZFSA also commissioned risk profile work on tuberculosis (Cressey et al, 2006)
and Campylobacter (Lake et al, 2007c) from red meat, and both were considered low
risk (Table 16). These were not examined in the MLA risk profile, as Australia has
been declared tuberculosis free and a definitive association of Campylobacter with
red meat could not be established (MLA, 2003a).
The risk from C. perfringens from meat consumed in the home was considered
medium (Table 17), with poor cooling and reheating the main contributing factors.
Problems with C. perfringens have arisen more in large-scale, catering-type
operations than in the home, where the spore forming bacteria have been allowed to
germinate and grow due to poor cooling of meat-based dishes.
Page 53 of 189
Table 16 – NZFSA risk profile outcomes examining hazards in meat
Hazard
Risk
Shiga toxin-producing
Escherichia coli in red meat
and meat products
Overseas studies have consistently linked human cases of
STEC infection and particularly E. coli O157:H7 to
consumption of red meat in the form of undercooked
hamburgers, not one case in New Zealand has been
associated with regulated foods.
(Lake et al, 2002a)
Toxoplasma gondii in red meat
and meat products
(Lake et al, 2002b)
Yersinia enterocolitica in pork
(Lake et al, 2004)
Mycobacterium bovis in red
meat
(Cressey et al, 2006)
Campylobacter jejuni/coli in
red meat
(Lake et al, 2007c)
Toxoplasma gondii is a protozoan parasite that causes
disease in humans with a range of outcomes including, at
worst, miscarriages. Cysts in the muscle tissue of meat
animals may result in infection when eaten. The
significance of human infections, especially congenital
toxoplasmosis, in New Zealand is unknown and has been
identified as a knowledge gap
Pigs are known to be frequently contaminated with
Y. enterocolitica, but effective cooking or pasteurisation will
eliminate Y. enterocolitica from foods. Pork consumption
has consistently been associated with yersiniosis in studies
in New Zealand and overseas, with cross contamination
from uncooked meats to RTE foods a potential source of
infection.
A proportion of human tuberculosis cases have been
caused by Mycobacterium bovis. While transmission of
tuberculosis to humans through consumption of M. bovisinfected meat is possible, no cases of this have been
confirmed in New Zealand and it is considered low risk.
Seventeen outbreaks of campylobacteriosis in New Zealand
from 1999 to 2004 have been associated (weakly) with red
meat consumption. Data in New Zealand indicates there is
low but consistent contamination across pork, beef, and
sheep meat. On this basis it is identified as a minor risk
factor for exposure to Campylobacter in New Zealand.
Page 54 of 189
Table 17 – Risk ranking for meat and meat products
Meat product
Severity 7
Effect of
production,
processing,
handling on
the hazard
↓↑→
Retail meats consumed in the home (steak, mince, chops, roast, fresh sausages)
Consumed
Toxoplasma
IB
Medium
No
↓freezing, →
undercooked/raw
gondii
Consumed
undercooked
Reheated roasts
Reheated roasts
Potential
pathogen
Poor cooling
7
8
Hazard
Probability
Growth
required
to cause
illness
Consumer
does
pathogen
reduction
step
Epidemiological
link
Risk
rating
Predicted
annual
number of
illnesses
(in
Australia) 8
Yes/No
Yes
High
EHEC
IB
Low
Yes
↓→
Yes
Yes
Medium
715 (242 in
pregnant
women)
No estimate
C. perfringens
S. aureus
Aeromonas
Mycobacterium
paratuberculosis
Bacillus
Yersinia
enterocolitica
III
III
III
III/IB
Low
Medium
Low
Low
Yes
Yes
Yes
N/A
↓↑
↓↑
↓↑
??
No
No
Yes
??
Yes
Yes
No
??
Medium
Low
Low
Low
No
No
No
No
III
III
Low?
Low??
Yes
Yes
↓↑
↓↑
Yes
Yes
??No
?
Low
Low
No estimate
No estimate
estimate
estimate
estimate
estimate
ICMSF (2002) defines the level of severity as follows:
− IA – Severe hazard for general population, life threatening or substantial chronic sequelae or long duration
− IB – Severe hazard for restricted populations, life threatening or substantial chronic sequelae or long duration
− II – High hazard incapacitating but not life threatening sequelae rare moderate duration.
− III – Moderate, not usually life threatening no sequelae normally short duration symptoms are self limiting can be severe discomfort.
Data from Sumner (2002) predicted annual numbers of illness per annum for the South Australia population (1.5 million), the MLA Risk Profile (MLA, 2003a) used an Australian population figure
of 19.7 million. These estimates have been extrapolated to the current population of Australia estimated by ABS (2009) as approximately 21.6 million, by multiplying by a factor of 14.4 and 1.1
respectively.
Page 55 of 189
Retail meats consumed in the home (steak, mince, chops, roast, fresh sausages)
↓↑
Assume 1% cross Salmonella
II/IB
Low
Yes
contamination
rate
↓↑
Assume 10%
Salmonella
II/IB
Low
Yes
cross
contamination
rate
↓↑
Assume 50%
Salmonella
II/IB
Low
Yes
cross
contamination
rate
Enterohaemorrhagic E. coli in hamburger
↓→
Hamburgers
EHEC
IA/IB
Low
No
↓→
Hamburgers EHEC
IA/IB
Low
No
assume 50%
undercooked
↓→
Hamburgers
Salmonella
II/IB
Low
Yes
Yes
Yes
Medium
583
Yes
Yes
High
5,830
Yes
Yes
High
29,370
Yes Yes
Yes
Yes
Low
Low
0
7
Yes
Yes
Low
0
adapted from Sumner (2002); MLA (2003a)
Page 56 of 189
Table 18 – Risk ranking for processed poultry meat products
Processed
meat
product
Hazard
Severity
Probability
Growth
required
to cause
illness
Consumer does
pathogen
reduction step
Epidemiological
link
Risk
rating
Predicted
annual
number of
illnesses (in
Australia) 9
Yes
Effect of
production,
processing,
handling on
the hazard
↓↑→
↓
Processed
chicken
Processed
chicken
Salmonella
II/IB
Low
No
Yes
High
864
Campylobacter
IB
Low
Yes
↓↑
No
Yes
High
86,400
adapted from Sumner (2002)
Table 19 – NZFSA risk profile outcomes examining hazards in poultry meat
Hazard
Risk
Salmonella (non-typhoid) in poultry (whole and
pieces)
(Lake et al, 2004)
Campylobacter jejuni/coli in poultry
(Lake et al, 2007a)
Salmonellosis is the second most frequently notified enteric disease in New Zealand. Poultry meat is
regarded as an important source of infection
Campylobacter jejuni/coli in mammalian and
poultry offals
(Lake et al, 2007b)
9
Campylobacter is the most frequently notified cause of enteric disease in New Zealand. Consumption of
chicken was linked with Campylobacter infection and several outbreaks of campylobacteriosis identified
undercooked chicken as the transmission vehicle
The consumption of poultry and mammalian offal is low in comparison to other meat types. However the
high prevalence of Campylobacter in raw sheep and chicken livers is of concern, especially when some
advice to consumers is to cook chicken livers "until they're pink in the middle" or "lightly sautéed". Offal
for pet food is frequently contaminated and handling may provide a risk of infection
Data from Sumner (2002) predicted annual numbers of illness per annum for the South Australia population (1.5 million). These estimates have been extrapolated to the current population of
Australia estimated by ABS (2009) as approximately 21.6 million, by multiplying by a factor of 14.4.
Page 57 of 189
Poultry meat
In the FSANZ scientific assessment of poultry meat, it was found there was
reasonable evidence to indicate poultry is the vehicle for a significant proportion of
campylobacteriosis and salmonellosis cases in Australia (FSANZ, 2006). This
conclusion was made on the basis of epidemiological data, results from
microbiological surveys of raw poultry carcase and outputs from a probabilistic
model. Sumner (2002) estimated large numbers of foodborne illness cases to be due
to processed chicken products, greater than 80,000 cases per annum from
Salmonella and Campylobacter in Australia (Table 21). Work commissioned by the
New Zealand Food Safety Authority has also found the presence of these organisms
on poultry to be a significant source of infection (Table 19).
Management of both Salmonella and Campylobacter requires an approach across
both primary production and processing. Good hygienic practices and good
agricultural practices are necessary prerequisites for the management of Salmonella
and Campylobacter, and appropriate hygiene and sanitation is required during
processing to minimise cross contamination between birds. Surveys of poultry pieces
available for retail sale show that a large proportion of poultry carries these
organisms, creating a risk of foodborne illness from consuming undercooked chicken,
but also the risk of cross contamination occurring in food preparation areas. FSANZ
(2005) found that the implementation of control measures to reduce the prevalence
and levels of Salmonella and Campylobacter by ten-fold at the end of processing
could result in a 74% and 93% reduction in the number of predicted cases of illness
respectively.
FSANZ identified the following significant factors contributing to contamination of
poultry meat with Salmonella and Campylobacter :
•
On-farm contamination with Salmonella is mainly due to contaminated feed
and water, environmental sources and transmission from contaminated eggs
•
Important on-farm risk factors for Campylobacter are the age of the birds and
environmental factors
•
The presence and amount of Salmonella on a chicken after processing largely
determines the likelihood of salmonellosis
•
Inadequate hand washing and food handling practices determine the
likelihood of human illness from Campylobacter
•
Adequate cooking is the main means of minimising the risk to human health
from both pathogens
The FSANZ scientific assessment found little evidence of public health risks
associated with chemical hazards from Australian poultry meat. The report concluded
that the current regulatory measures appear to adequately protect public health and
safety with respect to chemical hazards (FSANZ, 2006).
Game meat
Evidence suggests that the consumption of kangaroo meat and other game meat
present little risk as a source of foodborne illness when compared to other forms of
meat.
Page 58 of 189
Processed meats
Sumner (2002) stated that the highest risk products in the meat industry in South
Australia are smallgoods, predominantly due to pathogenic E. coli, Salmonella and
L. monocytogenes. The risk of L. monocytogenes from processed RTE meats in New
Zealand was examined by Lake et al (2002), who found that these products were a
significant route of infection in that country. The FDA/USDA risk assessment for
L. monocytogenes identified processed meats products or ‘deli meats’ as the highest
risk food from the 23 RTE foods examined in the USA (FDA/USDA, 2003). Deli meats
were the only food to be ranked as very high risk and when extrapolated to the
Australian population are predicted to be responsible for 133 cases of listeriosis per
annum (see Table 22). In addition, frankfurters that were not reheated were ranked
as high risk by the FDA/USDA in their risk assessment. However it is not believed
that this practice is as common in Australia as in the US. Pâté and meat spreads
were ranked as high risk on a per serving basis, predominantly due to the probability
of contamination with L. monocytogenes post cooking, but this did not correlate with
a high number of predicted illnesses due to low consumption rates.
The MLA risk profile examined different scenarios for processed meat products and
provided risk rankings and predicted numbers of illness (MLA, 2003a, summarised in
Table 21). It was predicted that processed deli meats were responsible for 43 cases
of listeriosis in Australia per annum. Although there are 50-60 cases of listeriosis
reported each year in Australia, it is estimated that due to under-reporting, the true
number is closer to 120 per year. Therefore, processed meats were considered to be
the source of approximately one third of listeriosis cases in any one year (MLA,
2006).
The MLA guideline Listeria monocytogenes in smallgoods: risks and controls (MLA,
2006) proposes measures to control post processing contamination with
L. monocytogenes in processed meat:
•
install effective GMPs and sanitation standard operating procedures (SSOPs),
particularly in post-cooking operations such as slicing/portioning and packing
•
incorporate antimicrobials into formulations of products which are intended
for slicing and packing as long shelf-life products
•
employ technologies for in-pack pasteurisation
In late 2008, the NSW Food Authority implemented national testing requirements for
sliced pre-packaged RTE meat products (Meat Standards Committee, 2008). This
Listeria management program involved the introduction of minimum finished product
and environmental testing to any facilities manufacturing these products (NSW Food
Authority, 2008).
The MLA risk profile (MLA, 2003a) and the work of Gilbert et al (2007) considered
the risk of pathogenic E. coli (STEC and EHEC) from UCFM products such as salami.
Both studies found that well controlled processes, including efficient fermentation
and a maturation producing a low pH and water activity, effectively controlled the
hazard (Table 20 and Table 21), with a 2-3 log reduction in E. coli. As a result, with a
well controlled process, it was predicted that no illnesses would result from these
products. However, if contaminated meat was used, and an unreliable process was
not able to reduce the hazard, then there may be up to 604 illnesses in a year (see
Page 59 of 189
Table 21). In addition, if susceptible members of the population consumed product
with high levels of pathogenic E. coli present there may be up to 125 cases per
annum. It was predicted that Salmonella may cause 11 illnesses per year from UCFM
products, while green runners used for casings of sausages and salami would not
cause any illness. Given the level of specialist skills and knowledge required to safely
make these products, specific requirements for the production of UCFM products are
included in Standard 4.2.3 – Primary Production and Processing Standard for Meat of
the Food Standards Code. Salmonella was considered a medium risk, while the risk
from L. monocytogenes in UCFM products was considered low, as it will not grow in
the product, however it may survive for extended periods. The risk from Toxoplasma
in UCFM products was also considered low, as the risk can be considerably reduced if
the meat is frozen before use, as this will kill the organism.
Kebabs were predicted to be a significant source of illness if allowed to be
recontaminated in the drip tray after cooking, with approximately 25,000 illnesses
per annum. Under normal conditions for cooking kebabs, or even when an extra cook
step was added, it was modelled that in 1% of cases, there may still be an element
of undercooking or some other mishandling to allow survival of Salmonella. In this
scenario, there were still 25 illnesses per annum predicted with kebabs as the cause.
A survey of NSW kebab retail outlets (Jansson et al, 2008) showed that 92% of
outlets undertook an extra cooking step after slicing the meat from the kebab.
Table 20 – NZFSA risk profile outcomes examining hazards in processed meats
Hazard
Listeria monocytogenes in
processed ready-to-eat meats
(Lake et al, 2002)
Shiga-like toxin producing
Escherichia coli in uncooked
comminuted fermented meat
products (Gilbert et al, 2007)
Risk
Several notified cases in New Zealand and an outbreak of
non-invasive listeriosis in February/March 2000 associated
with corned silverside and ham indicate that processed RTE
meats are a route of infection for listeriosis in New Zealand.
While uncooked comminuted fermented meat (UCFM)
products might appear to be a higher risk, well controlled
processing to lower the pH and water activity control
STECs.
Page 60 of 189
Table 21 – Risk ranking for processed meat products
Processed meat
product
Hazard
Severity
Probability
Growth
required
to cause
illness
Consumer
does
pathogen
reduction
step
Epidemiological
link
Risk
rating
Predicted
annual
number of
illnesses (in
Australia) 10;
Yes
Yes
Yes
Yes
Yes
Effect of
production,
processing,
handling on
the hazard
↓↑→
↓↑
↓↑
↓→
↓
↓
Deli meats
Terrines
Fresh sausage
Cooked sausages
Green runners
Kebabs
L. monocytogenes
L. monocytogenes
L. monocytogenes
L. monocytogenes
Salmonella
IB
IB
IB
IB
II/IB
Low
Low
Low
Low
N/A
No
No
Yes
No
Yes
Yes
Yes
No
No
No
High
Medium
Low
Low
Low
43
0.8
>0.01
0.04
0
Kebabs –
Salmonella
II/IB
Low
contaminated in
drip tray
Kebabs – normal
Salmonella
II/IB
Low
Kebabs – finished
Salmonella
II/IB
Low
with extra cook
step
Uncooked comminuted fermented meat (UCFM) products
Yes
↓→
Yes
Yes
High
27,500
Yes
Yes
↓→
↓→
Yes
Yes
Yes
Yes
Medium
Medium
28
28
Salami – general
population
Salami – vulnerable
population
Salami – unreliable
process
EHEC
IA/IB
II/IB
IB
IB
Low
Low
Low
Low
No
Yes
Yes
No
↓
↓
↓
↓freezing
No
No
No
No
Yes
Yes
No
No
Medium
Medium
Low
Low
1
12
>0.01
0
EHEC
IA/IB
Low
No
↓
No
Medium
125
EHEC
IA/IB
Low
No
↓
No
Yes – high level
contamination
Yes
High
604
Salmonella
L. monocytogenes
Toxoplasma
gondii
adapted from Sumner (2002); MLA (2003a)
10
Data from Sumner (2002) predicted annual numbers of illness per annum for the South Australia population (1.5 million), the MLA Risk Profile (MLA, 2003a) used an Australian population figure
of 19.7 million. These estimates have been extrapolated to the current population of Australia estimated by ABS (2009) as approximately 21.6 million, by multiplying by a factor of 14.3 and 1.1
respectively.
Page 61 of 189
Table 22 – Risk ranking for L. m onocytogenes- contaminated processed meats
Processed meat
product
Deli meats
Frankfurters, not
reheated
Pâté and meat spreads
Frankfurters reheated
Dry / semi-dry
fermented sausage
Risk
ranking
(per
serve)
High
High
High
Low
Low
Predicted cases of
listeriosis per
serve (in
Australia) 11
7.7 x 10-8
6.5 x 10-8
Risk
ranking
(per
annum)
Very high
High
Predicted
annual number
listeriosis cases
(in Australia) 12
133
2.5
3.2 x 10-8
6.3 x 10-11
1.7 x 10-11
Moderate
Low
Low
0.3
0.03
0
Conclusion
The production and processing of meat has a long history of successful regulation.
The preventative programs implemented by government and industry have improved
animal health to the point that many diseases are no longer present in Australian
animals. The meat food safety scheme under the Food Regulation 2004 requires
compliance with national meat standards, leading to ante-mortem and post mortem
inspections at abattoirs that have been effective in ensuring that meat produced in
NSW is safe and suitable for human consumption. The microbiological surveys of
meat production have shown a steady increase in the quality of meat produced.
However, epidemiological data suggests that the prevalence of Salmonella and
Campylobacter on raw poultry significantly contributes to the burden of foodborne
illness within the community, not only from the consumption of contaminated poultry
itself but the added potential for the introduction of these pathogens from poultry
into food preparation areas where they may be a source of cross contamination onto
RTE foods. Currently the food safety scheme requires compliance with the national
poultry meat standard, however this only provides control measures for the
processing sector. A whole chain approach is considered necessary, with control
measures introduced at the primary production level to reduce the prevalence of
these foodborne pathogens. With this aim in mind, FSANZ are currently finalising the
development of Standard 4.2.2 – Primary Production and Processing Standard for
poultry meat into Chapter 4 of the Food Standards Code. When finalised, this will be
adopted into NSW legislation. The contamination of processed meats with
L. monocytogenes continues to cause issues for meat processors, including a
substantial number of product recalls. Additional hygiene and sanitation measures,
including mandating the testing of finished product and food contact surfaces in high
risk processing facilities, such as those packaging sliced RTE meats, aims to minimise
contamination of this organism in product.
11
12
The risk per serving is inherent to the particular food category, and is therefore assumed to be the same in
Australia as that calculated for the USA (FDA/USDA, 2003). This is based on the assumption that consumption
patterns for these foods are identical in Australia and the USA. One significant difference would be that
frankfurters are not commonly eaten without reheating in Australia, with MLA (2003b) estimating that only 5%
are eaten without further cooking
The risk per annum has been adapted from USA population data contained in the FDA/USDA (2003) risk
assessment of 260 million and extrapolated to Australian population data of approximately 21.6 million (ABS,
2009) by dividing by a factor of 12
Page 62 of 189
References – Meat and meat products
ABARE [Australian Bureau of Agricultural and Resource Economics] (2007). Australian
Commodity Statistics 2007. Canberra. Retrieved 27 November 2008, from
http://www.abareconomics.com/publications_html/acs/acs_07/acs_07.pdf.
January 2009, from
D460/$File/48040_1995.pdf
ACMF [Australian Chicken Meat Federation] (2003). National Biosecurity Manual Contract
Meat Chicken Farming. Retrieved 14 January 2009, from
http://www.chicken.org.au/files/_system/Document/biosecuritychickenfarming.pdf
ACMF [Australian Chicken Meat Federation] (2008). Industry facts and figures. Retrieved 4
December 2008, from http://www.chicken.org.au/page.php?id=4.
Adak, G.K., Meakins, S.M., Yip, H., Lopman, B.A. & O’Brien, S.J. (2005). Diseases risks from
foods, England and Wales, 1996-2000. Emerging Infectious Diseases, 11, 365-72.
Ampt, P. & Owen, K. (2008). Consumer attitude to kangaroo meat products. RIRDC
Publication No 08/026. Retrieved 27 November 2008, from
http://www.rirdc.gov.au/reports/NAP/08-026.pdf.
Andrew, A.E. (1988). Kangaroo meat - Public health aspects. Australian Zoologist, 24(3), 138140.
APL [Australian Pork Limited] (2008) Annual Report 2007-08. Retrieved 4 December 2008,
from http://www.australianpork.com.au/pages/images/PORK%2012566%20AnnRep%200708%20Cover&Internals%20WEB%20V1.pdf.
Barton, M.D. & Robins-Browne, R.M. (2003). Yersinia enterocolitica. In Hocking A.D. (Ed.)
Foodborne Microorganisms of Health Significance (pp. 577-596). Australian Institute of Food
Science and Technology, Waterloo.
Bass, C., Crick, P. & Cusack, D. (2008). NSW domestic red meat abattoir evaluation – Final
report. Retrieved 4 December 2008, from
http://www.foodauthority.nsw.gov.au/_Documents/science/nsw_domestic_red_meat_abattoir
_evaluation.pdf.
Cassin, M.H., Lammerding, A.M., Todd, E.C.D., Ross W., McColl, R.S. (1998) Quantitative risk
assessment for Escherichia coli O157:H7 in ground beef hamburgers. International Journal of
Food Microbiology, 41(1), 21-44.
Cressey, P. Lake, R. & Hudson, A., & Nortje, G. (2006). Risk profile: Mycobacterium bovis in
red meat. Institute of Environmental Science and Research Limited report prepared for the
http://www.nzfsa.govt.nz/science/risk-profiles/FW0320_Mbovis_in_meat_final_May_2006.pdf
DAFF [Department of Agriculture, Fisheries and Forestry, Australian Government of] (2004).
Generic Import Risk Analysis (IRA) for pig meat - final import risk analysis report. Retrieved 5
December 2008, from http://www.daffa.gov.au/__data/assets/pdf_file/0018/18081/200401b.pdf
Doolittle, R. (2008, December 18). Maple Leaf settles listeria suits for $27M. The Toronto Star
Retrieved 19 January 2009, from http://www.thestar.com/business/article/555873
Eberhart-Phillips, J., Walker, N., Garrett, N., Bell, D., Sinclair, D., Rainger, W., & Bates, M.
(1997). Campylobacteriosis in New Zealand: results of a case-control study. Journal of
Epidemiology and Community Health 51:686-691
EFSA [European Food Safety Authority] (2007). Geographical BSE Risk (GBR) assessment
covering 2000-2006. List of countries and their GBR level of risk as assessed by the Scientific
Steering Committee and the European Food Safety Authority (EFSA). Retrieved 14 January
Page 63 of 189
2009, from
www.efsa.europa.eu/cs/BlobServer/Scientific_Document/GBR_assessments_table_Overview_
assessed_countries_2002-2006,0.pdf
EFSA [European Food Safety Authority] (2008). A quantitative microbiological risk assessment
on Salmonella in meat: Source attribution for human salmonellosis from meat. The EFSA
Journal 625, 1-32.
FAO/WHO [Food and Agriculture Organization of the United Nations / World Health
Organization] (2001). Risk characterization of Salmonella spp. in eggs and broiler chickens
and Listeria monocytogenes in ready-to-eat foods. FAO Food and Nutrition Papers – 72. Joint
FAO/WHO Expert Consultation on Risk Assessment of Microbiological Hazards in Foods.
Retrieved 30 October 2008, from http://www.fao.org/docrep/008/y1332e/y1332e00.HTM
FAO/WHO [Food and Agriculture Organization of the United Nations / World Health
Organization] (2003). Risk assessment of Campylobacter spp. in broiler chickens and Vibrio
spp. in seafood. FAO Food and Nutrition Papers – 75. Joint FAO/WHO Expert Consultation on
Risk Assessment of Microbiological Hazards in Foods. Retrieved 30 October 2008, from
http://www.who.int/foodsafety/publications/micro/en/aug2002.pdf
Food Science Australia & Minter Ellison Consulting (2002). National Risk Validation Project.
Final Report.
FSIS [Food Safety and Inspection Service, USDA] (2002). Comparative Risk Assessment For
Intact And Non-Intact (Tenderized) Beef: Executive Summary. Retrieved 14 January 2009,
from http://www.fsis.usda.gov/PDF/Beef_Risk_Assess_Report_Mar2002.pdf
FRSC [Food Regulation Standing Committee] (2007a). Australian standard for construction of
premises and hygienic production of poultry meat for human consumption. FRSC Technical
Report No 1. CSIRO publishing www.publish.csiro.au
FRSC [Food Regulation Standing Committee] (2007b). Australian standard for the hygienic
production of wild game meat for human consumption. FRSC Technical Report No 2. CSIRO
publishing www.publish.csiro.au
FRSC [Food Regulation Standing Committee] (2007c). Australia standard for the hygienic
production and transportation of meat and meat products for human consumption. FRSC
Technical Report No 3. CSIRO publishing www.publish.csiro.au
FSANZ [Food Standards Australia New Zealand] (2005). Scientific Assessment of the Public
Health and Safety of Poultry Meat in Australia is available. Retrieved 14 January 2009, from
http://www.foodstandards.gov.au/_srcfiles/P282_Poultry%20_%20DAR%20Attach3.pdf
FSANZ [Food Standards Australia New Zealand] (2006). Public health and safety of poultry
meat in Australia. – Explanatory summary of the scientific assessment., Canberra.
Gilbert, S., Lake, R., Hudson, A. & Cressey, P. (2007). Risk profile: Shiga toxin-producing
Escherichia coli in uncooked comminuted fermented meat products. Institute of
Environmental Science and Research Limited report prepared for the New Zealand Food
Safety Authority. Retrieved 14 January 2009, from http://www.nzfsa.govt.nz/science/riskprofiles/FW0611_STEC_in_UCFM_August_2007_Final.pdf
Microorganisms in Foods 7: Microbiological testing in food safety management. Kluwer
Academic/Plenum Publishers, New York.
Jansson, E., Bird, P., Saputra, T. & Arnold, G. (2008) 'Food Safety Survey of Retail Doner
Kebabs in NSW', Food Australia. 60 (3), 95-98.
Lake, R., Hudson, A. & Cressey, P. (2002a). Risk profile: Shiga toxin-producing Escherichia
coli in red meat and meat products. Institute of Environmental Science and Research Limited
Page 64 of 189
report prepared for the New Zealand Food Safety Authority. Retrieved 14 January 2009, from
http://www.nzfsa.govt.nz/science/risk-profiles/stec-in-red-meat.pdf
Lake, R., Hudson, A. & Cressey, P. (2002b). Risk profile: Toxoplasma gondii in red meat and
meat products. Institute of Environmental Science and Research Limited report prepared for
http://www.nzfsa.govt.nz/science/risk-profiles/toxoplasma-gondii-in-red-meat.pdf
Lake, R., Hudson, A. & Cressey, P. (2004). Risk profile: Yersinia enterocolitica in pork.
Institute of Environmental Science and Research Limited report prepared for the New Zealand
Food Safety Authority. Retrieved 14 January 2009, from
http://www.nzfsa.govt.nz/science/risk-profiles/yersinia-in-pork.pdf
Lake, R., Hudson, A., Cressey, P. & Gilbert, S. (2007a). Risk profile: Campylobacter jejuni/coli
in poultry (whole and pieces). Institute of Environmental Science and Research Limited report
prepared for the New Zealand Food Safety Authority. Retrieved 14 January 2009, from
http://www.nzfsa.govt.nz/science/risk-profiles/campylobacter.pdf
Lake, R., Hudson, A., Cressey, P. & Gilbert, S. (2007b). Risk profile: Campylobacter jejuni/coli
in Mammalian and Poultry Offals. Institute of Environmental Science and Research Limited
http://www.nzfsa.govt.nz/science/riskprofiles/FW0465_Campy_in_Offal_PVDL_final_comments_Mar_2007.pdf
Lake, R., Hudson, A., Cressey, P. & Gilbert, S. (2007c). Risk profile: Campylobacter jejuni/coli
in red meat. Institute of Environmental Science and Research Limited report prepared for the
http://www.nzfsa.govt.nz/science/riskprofiles/FW0485_Campy_in_red_meat_Final_sent_to_NZFSA_Jan_07.pdf
Lake, R., Hudson, A., Cressey, P. & Nortje, G. (2002). Risk profile: Listeria monocytogenes in
processed ready-to-eat meats. Institute of Environmental Science and Research Limited
http://www.nzfsa.govt.nz/science/risk-profiles/listeria-in-rte-meat.pdf
Lake, R., Hudson, A., Cressey, P. & Wong, T. & Gilbert, S. (2004). Risk profile: Salmonella
(non typhoidal) in poultry (whole and pieces). Institute of Environmental Science and
Research Limited report prepared for the New Zealand Food Safety Authority. Retrieved 14
January 2009, from http://www.nzfsa.govt.nz/science/data-sheets/salmonella-poultryupdate.pdf
Leech, A., Shannon, P., Kent, P., Runge, G., Warfield, B. (2003) Opportunities for Exporting
Game Birds. Rural Industries Research and Development Corporation (RIRDC). Report
Number 03/106. Retrieved 6 November 2009, from http://www.rirdc.gov.au/reports/NAP/03106.pdf
McEvoy, J.M., Sheridan, J.J. & McDowell, D.A. (2004). Major pathogens associated with the
processing of beef. In Smulders F.J.M & Collins, J. D. [Eds] Food safety assurance and
veterinary public health Volume 2. Safety Assurance during food processing pp 57-80.
Wageningen Academic Press. , Wageningen Netherlands
Meat Standards Committee (2002). Microbiological testing for process control in the meat
industry – guidelines. Retrieved 19 February 2009, from
http://www.primesafe.vic.gov.au/uploads/Microbiological%20Guidelines.pdf
Meat Standards Committee (2008). Regulatory guidelines for the control of Listeria. In NSW
Food Authority (2008) Listeria management program.
Page 65 of 189
MLA [Meat & Livestock Australia] (2000). The Microbiology of Australian Meat (1998). North
Sydney: Meat and Livestock Australia.
MLA [Meat & Livestock Australia] (2003a). Through chain risk profile for the Australian red
meat industry, PRMS.038c, part 1: risk profile. North Sydney: Meat and Livestock Australia.
MLA [Meat & Livestock Australia] (2003b). Guidelines for the safe manufacture of smallgoods.
North Sydney: Meat and Livestock Australia.
MLA [Meat & Livestock Australia] (2005). Microbiological quality of Australian beef and
sheepmeat – results of the industry’s third national abattoir study. North Sydney: Meat and
Livestock Australia.
MLA [Meat & Livestock Australia] (2006). Listeria monocytogenes in smallgoods: Risks and
controls. North Sydney: Meat and Livestock Australia.
MLA [Meat & Livestock Australia] (2008a). Fast facts 2008. Australia’s beef industry.
Retrieved 14 January 2009 from, http://www.mla.com.au/NR/rdonlyres/3EF73ECB-4FBB4455-A561-14CC636D7ADB/0/BeefFastFacts2008.pdf
MLA [Meat & Livestock Australia] (2008b). Fast facts 2008. Australia’s sheepmeat industry.
Retrieved 14 January 2009, from http://www.mla.com.au/NR/rdonlyres/70C05D4D-5D3E425D-96F7-4B973E5BFF55/0/SheepmeatFastFacts2008.pdf
NSW Food Authority (2008). Listeria management program. Retrieved 19 February 2009,
from http://www.foodauthority.nsw.gov.au/_Documents/industry_pdf/listeria-managementprogram.pdf
PISC [Primary Industries Standing Committee] (2006). Model Code of Practice for the Welfare
of Animals - Land Transport of Poultry. PISC Report 91.
Pointon, A., Sexton, M., Dowsett, P., Saputra, T., Kiermeier, A., Lorimer, M., Holds, G.,
Arnold, G., Davos, D., Combs, B., Fabiansson, S., Raven, G., McKenzie, H., Chapman, A. &
Sumner, J. (2008). A baseline survey of the microbiological quality of chicken portions and
carcasses at retail in two Australian states (2005 to 2006). Journal of Food Protection, 71,
1123-1134.
Pople, T. & Grigg, G. (1999). Commercial harvesting of kangaroos in Australia – background
paper. Retrieved 10 November 2008, from
http://www.environment.gov.au/biodiversity/trade-use/wildharvest/kangaroo/harvesting/index.html
Ross, T. & Shadbolt, C.T. (2001). Predicting pathogen inactivation in uncooked comminuted
fermented meat products. Report for Meat & Livestock Australia.
Wallace. R.B. (2003). Campylobacter in. In Hocking A.D. (Ed.) Foodborne Microorganisms of
Public Health Significance (pp. 311-331). Australian Institute of Food Science and
Technology, Waterloo.
Widders, P.R., Coates, K.J., Warner, S., Beattie, J.C., Morgan, I.R. & Hickey, M.W. (1995).
Controlling microbial contamination on beef and lamb during processing. Australian Veterinary
Journal, 72(6), 208-211.
WHO/FAO [World Health Organization/Food and Agriculture Organization of the United
Nations] (2002). Risk assessment of Salmonella in eggs and broiler chickens: Interpretive
summary. Retrieved 14 January 2009, from
www.who.int/foodsafety/publications/micro/salmonella/en/index/html
Page 66 of 189
Plant products food safety scheme
In 2000, the former SafeFood Production NSW commissioned Food Science Australia
to determine the relative food safety risks for various plant products produced and/or
marketed in NSW (FSA, 2000a). This work resulted in six products being ranked as
high risk due to microbiological hazards (Table 23), and formed the scientific basis
for the introduction of the Plant products food safety scheme into the Food
Regulation 2004. The scheme was developed to introduce minimum regulatory
requirements for businesses producing high risk plant products, and to implement
control measures to minimise the risks from the microbiological hazards associated
with these products.
Table 23 – Microbiological hazards associated with plant products
Plant product
Fresh cut vegetables – may be
consumed raw
Fresh cut vegetables – chilled,
MAP or extended shelf life
Vegetables in oil
Seed sprouts
Fresh cut fruit
Fruit juice / drink (unpasteurised)
High risk ranking
Pathogenic E. coli
Salmonella serovars
L. monocytogenes
L. monocytogenes
C. botulinum
C. botulinum
Pathogenic E. coli
Salmonella serovars
Pathogenic E. coli
Salmonella serovars
L. monocytogenes
Salmonella serovars
Pathogenic E. coli
Medium risk ranking
B. cereus
L. monocytogenes
Cryptosporidium parvum
Enteric viruses
adapted from FSA (2000a)
Fresh cut vegetables
Fresh cut fruits and vegetables are raw agricultural products that have been
processed by means of washing, trimming, cutting or slicing to make them ready for
consumption. Contamination of vegetables may occur during growth, harvest, or
processing. Under certain conditions microorganisms can also become internalised
within the vegetables. Conditions that promote internalisation of microorganisms
include damage to the natural structure (eg punctures, stem scars, cuts, splits) and
placing warm produce into cooler, contaminated wash water.
The actual process of cutting and/or removing the protective outer surfaces of the
plants may increase the potential for pathogenic bacteria to survive and/or grow.
Many vegetable products do not undergo a kill step that will completely eliminate
pathogens, however measures such as sanitising washes may be used to reduce
microbial contamination of pathogens.
Many fresh cut vegetables are packaged under modified atmosphere packaging
(MAP) and refrigerated to extend the shelf life. This form of processing may lead to
an increased risk with pathogens such as L. monocytogenes and psychrotrophic
strains of C. botulinum by enhancing the conditions for their survival and allowing
additional time for growth. MAP products may become fully anaerobic if the plant
tissue is actively respiring and uses up all the oxygen. As any competition from
aerobic spoilage organisms is inhibited, this may increase the opportunity for
anaerobic or facultative anaerobic pathogens to grow.
Page 67 of 189
Fresh cut fruit
Fresh fruit are normally perceived as low risk foods, as they tend to have a thicker
protective skin than most vegetables and most are harvested from trees or bushes.
The notable exceptions are melons and strawberries, which are considered higher
risk because they grow close to the ground and their surfaces may become
contaminated with soil.
Contamination of fruit may occur at any point from growing (soil, fertilisation,
irrigation water, animal/bird waste), through to harvesting, processing (including
washing), distribution, marketing and consumption. Many microbial pathogens
cannot survive or grow on most fruit due to the low pH environment. However,
melons and strawberries have relatively high pH which makes them more likely to be
a food safety hazard. In addition, the skin of rockmelon tends to be porous which
may allow the penetration of pathogens and agricultural chemicals into the fruit.
Melons are often dipped in a sanitising solution after harvest (FSA, 2000a).
Fresh cut fruits may be value added by peeling, chopping, slicing and packaging
(FSA, 2000a). Many fresh cut fruit are packaged under MAP and refrigerated to
extend the shelf life. With additional time, this can lead to an increased risk from
pathogens that are adapted to the acidic environment of fruit and are able to survive
and grow in these foods.
A range of bacterial and viral pathogens and enteric parasites have been identified as
being of concern in fresh cut fruit. The actual process of cutting and/or removing
protective outer surfaces of the fruit may increase the potential for pathogens to
survive and/or grow. Fruit pickers and handlers with infections are also an important
source of contamination.
Vegetables in oil
This product category includes a diverse range of vegetables and mixtures of
vegetables and herbs that may be used fresh, dried, roasted or acidified. Oil is added
to exclude air, which prevents discolouration of the vegetable. Although immersion of
vegetables in oil reduces the available oxygen in the container, contrary to popular
belief, it does not preserve the food. Some pathogenic bacteria are able to survive
and grow in reduced levels of oxygen and even under anaerobic conditions in the
absence of oxygen.
C. botulinum is the main pathogen of concern because of its ability to grow
anaerobically and it has been linked to outbreaks of illness from the consumption of
vegetables in oil. Vegetables may be contaminated by C. botulinum spores, which
are frequently associated with soil and processes such as cooking and acidification
may be insufficient to inactivate the spores or prevent their germination and growth.
Acidification to below pH 4.6 should prevent outgrowth, however more than one
hurdle is recommended as a safeguard.
Seed sprouts
Seed sprouts are usually consumed raw and include alfalfa, mung bean, chickpeas,
cress, fenugreek, soy, lentils, sunflower, onion and radish. Seeds for sprouting
generally do not receive any special treatment during harvesting and transport and
so may become contaminated with pathogenic organisms in the field or during
harvesting, handling, processing and distribution. While some bean sprouts may be
cooked prior to consumption, many others are consumed raw, for instance with
salads.
Page 68 of 189
The microbiological pathogens frequently found associated with seeds for sprouting
include B. cereus, Salmonella serovars, and E. coli and these organisms have also
been implicated in foodborne illness outbreaks. The rough surfaces and cracks in the
seed may protect the pathogens from microbiocidal treatments and may make
detection during routine analysis difficult. High levels of organic matter also reduce
the effectiveness of chlorine treatments during seed washing and seed sprouting.
Bacterial populations of 102-107 cfu/g have been observed on seeds for sprouting
and this natural population can rapidly increase under the high moisture and
moderate temperature conditions used in sprouting facilities. Microorganisms may
also become internalised in the sprout during growth so sanitising wash treatments
of sprouted seeds are not likely to be effective (FSA, 2000a).
Unpasteurised fruit juice
Fruit juices are made by extracting fruit (citrus juices) or by macerating fruit (grape,
cherry, berry, apple juice, etc). This may be followed by clarification, filtration,
pasteurisation, and/or other processes to reduce the microbial load. In recent years
there has been a trend to produce ‘natural’ fruit juices containing no preservatives
and receiving little or no heat treatment.
Any microorganisms present on the surface of fruit may potentially contaminate the
juice made from it. Bacterial pathogens are unlikely to grow due to the low pH but
some bacteria, viruses or protozoa may be able to survive for extended periods. The
length of time the microorganism may survive is dependent on the pH of the juice,
storage temperature and the physiological state of the microorganism. Some
Salmonella serovars and strains of pathogenic E. coli are known to be particularly
acid tolerant, with this response thought to be activated by previous exposure to
sub-lethal pH values.
Apple and pear juice are can become contaminated by the mycotoxin patulin which is
produced by several Penicillium and Aspergillus species. P. expansum appears to be
the main patulin producer in apples and apple products. Since patulin is concentrated
in the rotting tissue of fruit, it is a good indicator of the quality of fruit used to make
the juice.
The acidic nature of fruit juices makes them corrosive to metals. To avoid potential
chemical contamination, only stainless steel or corrosion resistant vessels should be
used to store these products. Other metals such as copper can leach into the
beverage during storage.
Exposure assessment
Production data
Leafy salad vegetables, such as lettuce, rocket and baby spinach are the most
common products in the fresh cut category, contributing towards an estimated
national production value of $44 million for the year 1997–98 (Szabo & Coventry,
2001).
The Regulatory Impact Statement (RIS) prepared for the Food Regulation 2004,
based on limited industry information, estimated annual NSW consumption of the
fresh cut fruit and vegetables (NSW Food Authority, 2004) as:
•
11,000 tonnes fresh cut vegetables, with a high proportion imported from
Victoria and Queensland
•
150 tonnes of fresh cut fruit
Page 69 of 189
•
Approximately 1000 tonnes of vegetables in oil, with the vast majority
imported from overseas and interstate and
•
Between 2100 and 2600 tonnes of seed sprouts
Subsequent recent surveys by the NSW Food Authority of the NSW sprout industry
suggest that 2007/08 production was in the order of 3630 tonnes, with some of this
product being sold interstate. NSW fruit juice suppliers suggest that manufacture of
unpasteurised fruit juices occurs at relatively low volume, about 100,000 L/year, not
including juices prepared in retail premises (NSW Food Authority, unpublished).
Consumption of plant products
Consumption data for fruits and vegetables from the National Nutrition Survey are
summarised in Table 24 (ABS, 1995). During the period 1997-98 and 1998-99, fruit
and fruit products (including fruit juices) consumption increased by 8.3% from 124.7
kg per capita to 135.0 kg. In the same period, imports for oranges and other citrus
fruit rose by more than 62% (ABS, 2000).
Consumption of vegetables has shown a steady 9.4% increase over the last decade.
Per capita consumption of tomatoes showed a significant increase from 20.9 kg in
1997-98 to 24.9 kg in 1998-99, a rise of 19%. The category of other vegetables
showed an increase in consumption in 1998-99 of 4.6% to 25.1 kg per person.
Data from the Australian 1995 National Nutrition Survey (ABS, 1995) indicates that
fruit juices and drinks are consumed in significant amounts by a large proportion of
the population. Approximately 35% of all respondents consumed fruit juices and
drinks with the mean consumption being 250mL per day.
Page 70 of 189
Table 24 – Consumption of fruits and vegetables in Australia
Sex
Age
Male
Male
Male
Male
2-3
4-7
8 - 11
12 15
16 18
19 24
25 44
45 64
65+
2-3
4-7
8 - 11
12 15
16 –
18
19 24
25 44
45 64
65+
Male
Male
Male
Male
Male
Female
Female
Female
Female
Female
Female
Female
Female
Female
Proportion
of persons
consuming
fruit
products and
dishes 13
(%)
77.6
65.6
56.4
49.9
Median daily
intake for
consumers of
fruit products
and dishes
(g/day)
153.6
168.0
166.0
167.2
Proportion of
persons
consuming
vegetable
products and
dishes 14
(%)
68.1
72.7
77.0
78.8
Median daily
intake for
consumers of
vegetable
products and
dishes (g/day)
92.1
118.0
165.0
223.0
39.9
172.0
83.1
253.6
31.9
179.2
84.7
271.3
45.8
210.0
86.6
263.0
59.5
229.0
91.0
297.8
69.6
75.4
72.8
62.5
58.0
202.0
140.0
166.0
150.8
172.0
91.7
79.2
79.7
77.0
85.9
280.4
95.2
122.5
158.0
180.8
41.1
191.0
85.8
185.0
41.4
166.0
86.5
220.5
55.0
188.4
88.0
216.1
69.8
192.0
91.0
258.5
75.6
196.0
91.5
239.3
The consumption data does not provide information on how much unpasteurised
juice is consumed, however the Australian Fruit Juice Association believes that
approximately 95% of juice sold has undergone some form of pasteurisation process.
13
Fruit products and dishes are defined in the National Nutrition Survey (ABS, 1995) as including the following:
- Pome fruit, berry fruit, citrus fruit, stone fruit, tropical fruit, other fruit
- Mixtures of two or more groups of fruit
- Dried fruit, preserved fruit
- Mixed dishes where fruit is the major component
14
Vegetable products and dishes are defined in the National Nutrition Survey (ABS, 1995) as including the
following:
- Potatoes, cabbage, cauliflower and similar brassica vegetables, carrot and similar root vegetables, leaf
and stalk vegetables, peas and beans, tomato and tomato product, other fruiting vegetables
- Other vegetable and vegetable combinations
- Dishes where vegetable is the major component
Page 71 of 189
Prevalence of hazards in plant products
There have been a small number of surveys of Australian plant products. Arnold &
Coble (1995) in a broad survey of NSW food found 1/54 samples (1.9%) of RTE
salads and vegetables positive for L. monocytogenes.
Szabo et al (2000) tested 120 minimally processed, cut and packaged lettuce
samples. Three samples (2.5%) were positive for L. monocytogenes, 66 samples
(55%) were positive for Aeromonas hydrophila or A. caviae and 71 samples (59%)
were positive for Y. enterocolitica.
The Victorian Department of Human Services (DHS) surveyed the microbiological
quality of freshly squeezed juices from retail businesses across the state (Victorian
DHS, 2005). L. monocytogenes was detected in 1/291 samples (0.3%), but the level
was sufficient to classify the sample as potentially hazardous. E. coli was detected in
7/291 samples (2.4%). Salmonella and coagulase positive S. aureus were not
detected.
The Western Australian Department of Health (WA Health, 2006) tested 261 samples
of sprouted seeds from retail stores. E. coli was detected in 7 samples (2.7%), while
Listeria and Salmonella were not detected in any samples.
The NSW Food Authority undertook a small survey in 2006 to determine the safety of
fresh cut vegetables sold in NSW. E. coli was detected in 1/119 samples (0.8%),
while Salmonella, L. monocytogenes and verotoxigenic E. coli (VTEC) were not
detected in any samples (NSW Food Authority, unpublished).
The Authority has also undertaken several surveys of seed sprouts. In 2005, all 30
samples were found to be microbiologically acceptable. In 2006, 1/36 samples
(2.7%) was found to be potentially hazardous due to the presence of VTEC and a
further two samples were categorised as unsatisfactory due to elevated levels of
E. coli. A more extensive survey in 2008 of 122 samples found 99.2% of samples
were microbiologically acceptable, with a single sample categorised as unsatisfactory
due to B. cereus at a level of 5500 cfu/g (NSW Food Authority, 2008).
There has been considerable international interest in the safety of plant products.
O’Brien et al (2000) prepared a discussion paper on the microbiological status of RTE
fruit and vegetables for the UK Advisory Committee on the Microbiological Safety of
Food (ACMSF). The report provided a summary of foodborne illness outbreaks and
surveys of plant products. The report concluded that while contamination of raw
vegetables usually occurs at low prevalence, it is pervasive.
The Food Safety Authority of Ireland (FSAI) surveyed the bacteriological safety of a
range of plant products as part of a European Commission coordinated program
(FSAI, 2003). Pre-cut fruit and vegetables had samples classed as
unacceptable/potentially hazardous due to the presence of Salmonella in 1/529
samples (0.2%) and L. monocytogenes in 1/344 samples (0.3%). Qualitative tests
found 21/513 samples (4.1%) positive for L. monocytogenes. No sprouted seeds
samples were classed as unacceptable or potentially hazardous. L. monocytogenes
was detected in 1/26 samples (3.8%). No problems were detected with
unpasteurised fruit and vegetable juices.
A similar European Commission program surveyed pre-packed mixed salads from
retail premises in the UK for L. monocytogenes (Little et al, undated).
L. monocytogenes was detected in 4.8% of samples collected. A parallel survey by
the FSAI included Salmonella testing in the survey design (FSAI, undated).
Qualitative analysis showed L. monocytogenes was present in 19/714 samples
Page 72 of 189
(2.7%). Quantitative analysis detected two samples with L. monocytogenes at levels
exceeding 100 cfu/g, however Salmonella was not detected in any sample.
Little & Gillespie (2008) summarised microbiological results of surveys of prepared
salads and fruit examined in the UK. No isolations of E. coli O157 or Campylobacter
were reported. Five of 3852 samples (0.1%) of bagged salad vegetables were
positive for Salmonella but other commodities were negative. L. monocytogenes and
E. coli were detected in most commodities surveyed, usually at low incidence.
Crepet et al (2007) used statistical techniques on 165 prevalence studies and
concentration data from 15 studies of L. monocytogenes in fresh vegetables to
estimate an overall probability of significant counts being found in the products.
Their mathematical method required a minimum of one positive sample in each
survey. However, as some survey sets had no actual detections, this change was
made to data sets to accommodate the statistical analysis. Acknowledging this
deliberate overestimation, the authors calculated the probability of sample
contamination with L. monocytogenes exceeding 10 cfu/g as 1.4%, exceeding 100
cfu/g as 0.6% and exceeding 1000 cfu/g as 0.2%.
Foodborne illness outbreaks from plant products
An indication of the exposure to hazards in plant products is provided by an
examination of the Australian foodborne illness outbreaks between 1995 and 2008
attributed to fresh produce and plant products, summarised in Table 25 (details of
each outbreak are included in Table 67 of Appendix 3). Prior to this, two other
Australian outbreaks of significance brought plant products into the spotlight as a
significant source of foodborne illness. In NSW in 1989 there were three separate
outbreaks from fruit salad due to Salmonella Bovismorbificans traced to a single NSW
salad manufacturer (Biffin & McCarthy, pers comm), while in 1991 a nationwide
outbreak from Norovirus was attributed to the consumption of unpasteurised orange
juice. The juice was served on airline flights and was responsible for more than 3000
cases of illness (Foodlink, 2002). In addition, the risk of listeriosis from plant
products was highlighted by an outbreak of listeriosis from contaminated fruit salad
in NSW aged care facilities and hospitals in the Hunter Valley area. Through 19981999, six deaths of elderly patients occurred and nine were affected (this outbreak is
included in outbreak data for the section on the Vulnerable persons food safety
scheme).
Internationally, there have been many examples of outbreaks that have been
attributed to plant products. Sivapalasingham et al (2004) summarised the outbreaks
attributed to fresh produce in the USA from 1993 to 1997. The authors identified 190
produce-associated outbreaks, resulting in 16,058 illnesses, 598 hospitalisations and
eight deaths. They report that produce-associated outbreaks were an increasing
proportion of all reported foodborne outbreaks with a known food cause, rising from
0.7% in the 1970s to 6% in the 1990s. Salad, lettuce, juice, melon, sprouts, and
berries were the fresh produce most frequently implicated. Sivapalasingham et al
(2004) also recognised Cyclospora and E. coli O157:H7 as novel causes of foodborne
illness from plant products.
Page 73 of 189
Table 25 – Summary of foodborne illness outbreaks attributed to plant products
Hazard
Salmonella serovars
Campylobacter spp.
Norovirus
Shigella spp.
Viral
Unknown
Total
Australian
outbreaks
(1995–2008)
11
2
1
1
1
10
26
Cases
941
128
18
55
61
192
1395
33
0
0
0
0
2
35
1
0
0
0
0
0
1
DeWaal et al (2009) also reviewed outbreaks in the USA from fruit and vegetables
for the period 1990 to 2005. They reported greens-based salads contaminated with
norovirus as the most common cause of outbreaks, followed by lettuce with
norovirus, sprouts with Salmonella, fruit with norovirus, greens-based salads with
Salmonella and melon with Salmonella. Produce-related outbreaks resulted in an
average of 47.8 cases, which is higher than reported for outbreaks from poultry, beef
and seafood.
Doyle & Erickson (2008) presented an overview of the problems associated with
fresh produce. Four further outbreaks that occurred in 2006 were discussed; an
outbreak traced to fresh spinach contaminated with E. coli O157; salmonellosis
traced to tomatoes and two outbreaks linked to lettuce contaminated with E. coli
O157:H7.
Little & Gillespie (2008) reviewed outbreaks related to prepared salads in England
and Wales in the period 1992 to 2006. The authors reported 82 outbreaks from
prepared salads with 3434 people affected, 66 hospitalisations and one death.
Peck et al (2008) reviewed the potential for growth and neurotoxin formation by –
non-proteolytic C. botulinum in short shelf-life foods designed to be chilled. Their
foodborne illness examples included seven outbreaks of botulism in products of plant
origin. The implicated products were commercial garlic-in-oil, hazelnut yoghurt
(attributable to the hazelnut conserve, see the section on the Dairy food safety),
restaurant potato dip, restaurant aubergine dip, commercial black bean dip,
commercial hummus and commercial refrigerated carrot juice. Temperature abuse
was suspected to be contributing factor in four of the outbreaks.
The following international outbreaks warrant individual mention because of either
their size or novel cause:
•
In 1996 an outbreak of E. coli O157:H7 infection occurred among
schoolchildren in Sakai City, Osaka, Japan. The outbreak was attributed to
white radish sprouts served in a centralised luncheon program servicing 56
schools. Over 8000 children developed symptoms and 398 children were
hospitalised. Two further incidents of E. coli O157:H7 in neighbouring areas
were also related to white radish sprouts. All the implicated sprouts were
traced back to one farm (Michino et al, 1999). This illustrates the size of an
outbreak that can result when a hazard becomes a reality in a centrally
processed and is a widely distributed product.
•
In 1998 an outbreak of cyclosporiasis (a gastrointestinal illness caused by the
parasite Cyclospora) occurred in Ontario, Canada. A further 12 clusters of
cyclosporiasis were identified with a total of 192 cases. The investigation
linked the clusters to raspberries imported from Guatemala. Outbreaks of
Page 74 of 189
cyclosporiasis in North America during the spring of 1996 and 1997 were also
linked to Guatemalan raspberries. This is an example of repeated outbreaks
attributable to parasites due to failures in hygiene and sanitation during the
growing and handling of raspberries (MMWR, 1998).
•
In 2003 an outbreak of Hepatitis A was traced to a restaurant in
Pennsylvania, USA and linked to the consumption of green onions (similar to
shallots). Early in the outbreak 555 cases had been identified and three
people died. The report noted that green onions require extensive handling
during harvesting and preparation for packing. Contamination by Hepatitis A
virus (HAV) could occur by contact with infected workers or contaminated
workers (MMWR, 2003). This is a large outbreak of viral illness attributable to
fresh produce.
•
In 2006 a multi-state outbreak of E. coli O157:H7 attributed to consumption
of fresh bagged spinach occurred in the USA. By January 2007, 205 cases
had been reported with 103 hospitalisations and 31 cases of haemolytic
uraemic syndrome (HUS) and 3 deaths confirmed. Contamination was traced
back to one farm. While no definitive determination of how the pathogens
contaminated the spinach could be made, the presence of wild pigs near the
growing fields and the irrigation wells were determined to be environmental
risk factors. Processing of the spinach included washing, did not eliminate the
problem and may have facilitated the spread of pathogens from contaminated
to uncontaminated spinach (California Food Emergency Response Team,
2007). This is an example of a widespread outbreak of severe bacterial illness
attributable to hygiene failures in the growing and processing of spinach.
•
In 2007, 55 cases of Salmonella Senftenberg infection in England and Wales
were linked to fresh basil. Scotland, Denmark, the Netherlands and the USA
reported 19 further cases with the outbreak strain. Eight samples of fresh
packed basil from Israel tested positive with the same strain. Microbiological
evidence suggested an association between contamination of fresh basil and
the cases of Salmonella Senftenberg infection, leading to withdrawal of basil
from all potentially affected batches from the UK market (Pezzoli, 2008).
•
In 2008 a large outbreak of Salmonella Saintpaul in the USA and Canada was
associated with multiple raw produce items. As at August 2008, 1442 people
had been affected, with at least 286 hospitalisations and the outbreak might
have contributed to 2 deaths. The epidemiological data suggested the major
vehicle for the spread of the pathogen was jalapeno peppers. However,
serrano peppers were also considered to be a vehicle, and early in the
outbreak tomatoes were considered a source. Contamination of produce may
have occurred on the farm or during processing or distribution. The outbreak
strain of Salmonella has been found in one growing area and an associated
packing facility in Mexico (MMWR, 2008). This is the largest culture confirmed
outbreak in the USA in the last decade. As many persons with Salmonella
illness do not seek care or have stool specimens tested, many more
unreported illnesses may have occurred.
Page 75 of 189
As previously discussed, the Food Science Australia plant products scoping study
ranked five specific plant product as high risk due to specific pathogens (FSA,
2000a), these are discussed as follows:
Fresh-cut vegetables and fresh cut fruit
Survey data shows that L. monocytogenes occurs in cut vegetables at low prevalence
and usually at low levels. Lake et al (2005) presented data showing that
L. monocytogenes can grow in a range of vegetables, however growth is typically
slow at refrigeration temperatures but numbers can increase by several logs in some
commodities stored at 10°-15°C for 7-10 days. The potential for growth in
refrigerated short shelf-life products would seem to be low. These products have no
final cooking process to eliminate contamination. Where product is packaged in MAP,
the potential longer shelf life increases the potential for pathogen growth.
Pathogenic Escherichia coli
The potential exists for pathogenic E. coli to be present on vegetables via direct or
indirect contamination with ruminant faeces or from food handlers that carry the
organism in their gut. However, surveys of pre-cut vegetables and salads, other than
in Mexico, rarely, if ever, detect pathogenic E. coli.
Gilbert et al (2006) reviewed the dose response estimates for E. coli O157:H7 and
original estimates of infectious dose were less than a few hundred cells. Later work
estimated the probability of infection from exposure to differing numbers of cells.
One model predicted a dose of 5.9 x 105 organisms would result in infection in 50%
of consumers, while the probability of illness from 100 organisms was 2.6 x 10-4. A
second study calculated a median dose (50% of people exposed become
symptomatic) of 1.9 x 105 and a probability of 6 x 10-2 of infection when exposed to
100 cells. An analysis of data from the Sakai City elementary school outbreak with
E. coli O157:H7 indicates much higher probabilities of infection at lower doses than
previous models. Gilbert et al (2006) also reported dose-response for E. coli O111
and O55. The dose for infection of 50% of the exposed population was 2.6 x 106
organisms. The probability of illness when exposed to 100 cells was 3.5 x 10-4.
Gilbert et al (2006) state that the organism will grow on leafy vegetables at
temperatures above 7°C. However, due to the low infectious dose of the organism in
food, growth may not be required to cause illness.
Salmonellae
Jay et al (2003) included data on the incidence of salmonellae in fruit, vegetables
and spices with the prevalence shown to be below 10%. They note that numbers of
salmonellae on raw vegetables are usually <1 cfu/g, but numbers as high as 240
cfu/g have been found on Dutch endive. Jay et al (2003) also includes information
about an outbreak in Germany traced to paprika and paprika powdered potato chips
which resulted in an estimated 1000 cases of salmonellosis. The numbers of
salmonellae detected in the food were very low, around 2.5 Salmonella cfu/g in the
paprika and 0.04-0.45 Salmonella cfu/g of chips.
The risk of botulism is increased for products packaged in MAP, with the longer shelf
life increasing the potential for spore germination and pathogen growth. Food
Science Australia rated the risk of this pathogen / product pair as high (FSA, 2000a).
The contributing factors were the low dose required to cause illness, the severity of
the illness, the fact that processing increases the risk and the existence of an
Page 76 of 189
epidemiological link. That rating remains appropriate, particularly as longer shelf life
vegetable products are becoming more available.
Vegetables in oil
The US Food and Drug Administration (FDA, undated) lists a history of botulism
attributed to inadequately acidified foods and notes that products processed by 29
firms were found to be inadequately acidified. The FDA concluded that the evidence
demonstrated that certain manufacturers of acidified foods did not realise the
importance of adequate pH control. This resulted in the development of a specialised
regulation for acidified foods in Title 21 of the Code of Federal Regulation (21 CFR
114).
Despite the acidified foods regulation being published in 1979, two serious outbreaks
of botulism were reported in the 1980s in Canada and the USA. Chopped garlic in oil
was clearly identified as the source of botulism toxin (St Louis et al, 1988). The
concern about vegetables in oil and botulism remains current. The products are
popular and home production is common. According to Food Science Australia (FSA,
2000b), two false assumptions persist about vegetables in oil:
•
That the addition of oil has a preservative effect
o
•
Incorrect. The only function of the oil is to prevent oxidation from air in
the container which can lead to discolouration of some foods. By
excluding air from the surface, this establishes anaerobic conditions
which actually favour the growth of some types of bacteria, including
C. botulinum.
That some herbs and spices, and especially garlic, have significant antimicrobial properties
o
Incorrect. The preservative effect of these materials is slight and
inconsistent as outbreaks of botulism in Canada and the USA have
demonstrated.
While acidification to a pH less than 4.6 would adequately control the outgrowth of
C. botulinum, refrigeration is also used in some cases as an additional hurdle.
Seed sprouts
Outbreak investigations have identified several factors that affect the microbiological
safety of sprouted seeds. To date, contaminated seeds have been the likely source
for most outbreaks. Seed contamination could have occurred at the farm, seed
processor, or sprouting facility. The hydrophobic surface of seeds makes sanitation
and removal of contaminating microorganisms difficult. Conditions during sprouting
(time, temperature, aw, pH and nutrients) are ideal for growth of pathogenic bacteria
leading to an increased risk.
The majority of outbreaks caused by consumption of juice have been attributed to
the use of fruit that has been contaminated by animal faeces. Orchards are often
located near livestock or wildlife with the potential for microbial contamination.
Contamination of juice is more likely to occur where the skin or peel of the fruit is in
contact with the juice during processing.
Page 77 of 189
Fresh-cut vegetables and fresh cut fruit
To date, there has been no epidemiological evidence to link cases of
L. monocytogenes infection in Australia with fresh cut vegetables. As such, there is
sparse outbreak data to support the high risk rating allocated by Food Science
Australia (FSA, 2000a). The FDA/USDA (2003) quantitative risk assessment on
L. monocytogenes assigned low relative risk rankings to fruits, vegetables and delitype salads (Table 26). The report acknowledged the diversity of the product group
and supported further study. While it appears the probability of infection is low, even
for persons vulnerable to listeriosis, the consequences of the illness remain severe.
This was graphically demonstrated by the Hunter Valley outbreak where six persons
died from consumption of Listeria-contaminated fruit salad. The high risk rating is
also applied to modified atmosphere products (MAP) that are stored for extended
periods. The potential for growth in storage increases the ranking for MAP
vegetables and salads.
Pathogenic Escherichia coli
There have been a number of E. coli outbreaks attributed to this group of products
around the world. Consequences of illness are potentially severe with high rates of
hospitalisation and long terms effects such as HUS and kidney problems. Food
Science Australia (FSA, 2000a) rated the risk as high, while Gilbert et al (2006)
placed pathogenic E. coli in the highest severity category but lowest incidence
category for New Zealand foods. It was concluded that it is essential that efforts
continue to prevent the likelihood of foodborne transmission from this group of
organisms.
Table 26 – Risk ranking for plant products contaminated with Listeria
m onocytogenes
Plant product
Vegetables
Fruits
Deli-type salads
Risk
ranking
(per
serve)
Low
Low
Low
Predicted cases of
listeriosis per
serve
(in Australia) 15
2.8 x 10-12
1.9 x 10-11
5.6 x 10-13
Risk
ranking
(per
annum)
Low
Low
Low
Predicted annual
number of
listeriosis cases
(in Australia) 16
0.02
0.08
0
Salmonella serovars
Food Science Australia rated the risk of Salmonella in these products as high risk,
based on the severity of the illness and no consumer cooking step to eliminate the
hazard (FSA, 2000a). Basset & McClure (2008) rated Salmonella serovars as a
significant hazard for both fruit and vegetables based on similar criteria to Food
Science Australia, but note that growth in the product is not required for illness to
15
16
patterns for these foods are identical in Australia and the USA.
Page 78 of 189
eventuate. This appears consistent with the many outbreaks attributed to products in
which Salmonella might survive but not grow.
Food Science Australia (FSA, 2000a) rated the risk of C. botulinum in these products
as high. The contributing factors were the severity of the illness, the fact that
processing and packaging in MAP may increase the risk and the existence of an
epidemiological link. There is no domestic epidemiological evidence to support the
high risk ranking but, to date, longer shelf life vegetable products have had limited
availability.
Vegetables in oil
There appears clear potential for products prepared without appropriate control
measures to result in a poorly acidified product, with potential to cause severe illness
from pathogens such as C. botulinum. These products are sometimes prepared by
small and medium enterprises, which is considered to increase the risk if knowledge
of food safety controls is not adequate.
Seed sprouts
The conditions during sprouting (time, temperature, water activity, pH and nutrients)
are ideal for growth of pathogenic bacteria such as Salmonella and pathogenic E. coli
leading to seed sprouts being considered a high risk product (FSA, 2000a). The
potential for growth of pathogenic organisms during sprouting increases the risk
substantially, and there is epidemiological evidence to demonstrate that
contamination does occur. The implementation of control measures, such as
sanitation of seeds prior to sprouting, may lower the prevalence of pathogens.
The high risk ranking of unpasteurised juice by Food Science Australia is appropriate
(FSA, 2000a). The potential sources of contamination are virtually identical as for
fresh cut fruit, and there is strong epidemiological evidence to justify the risk. The
two large scale outbreaks in Australia in 1991 and 1999, due to contamination of
unpasteurised juice with Salmonella serovars have clearly demonstrated the potential
for unpasteurised juice to cause illness.
Conclusion
The introduction of a plant products food safety scheme into the Food Regulation
2004 targeted the five plant products categorised as high risk by the Food Science
Australia scoping study (FSA, 2000a). Minimum food safety control measures were
introduced with the aim of avoiding outbreaks of foodborne illness from these
products.
While plant products such as fresh cut fruit and vegetables generally have an image
as healthy foods and form an important part of a healthy nutritious diet, the
occurrence of several large scale outbreaks of foodborne illness in the US affecting
thousands of consumers highlights the potential risks associated with these products.
Due to the increasing demand for convenience foods from consumers, the market
share of pre-packed fresh cut fruits and vegetables on supermarket shelves has
increased dramatically in the last several years, therefore it is important that food
safety control measures are in place to ensure that the consuming public is
protected.
In addition to pre-packaged salads, there has been a history of unpasteurised juice
causing two large outbreaks in Australia, while seed sprouts have a history of
Page 79 of 189
causing foodborne illness outbreaks overseas and within Australia. While the history
associated with vegetable in oil products does not involved large outbreaks, there
exists the potential for severe illness, from pathogens such as C. botulinum, if these
products are not produced in a controlled manner. The food safety schemes
requirement for businesses producing plant products to implement a food safety
program means that appropriate control measures are applied, and that verification
of those controls occurs at regular intervals through testing of finished product.
While the Authority has a regulation in place covering the high risk plant products,
increasingly overseas there have been a number of large scale foodborne illness
outbreaks associated to intact fruit and vegetables, such as leafy greens, spinach
and rockmelon. While this has not occurred to date in Australia, the Authority will
continue to work with the Department of Primary Industries and the horticulture
industry to ensure food safety controls, such as control over the use of biosolids,
continue to be employed across the entire horticulture sector.
Page 80 of 189
References – Plant products
January 2009, from
D460/$File/48040_1995.pdf
ABS [Australian Bureau of Statistics] (2000). 1997-98 and 1998-99 Apparent consumption of
foodstuffs Australia. Australian Bureau of Statistics. Retrieved 12 December 2008, from
http://www.ausstats.abs.gov.au/ausstats/subscriber.nsf/0/3CDE7A3E9BEF68F3CA256982007
E8CD6/$File/43060_1997-98%20and%201998-99.pdf
Allens Arthur Robinson (2003), Salmonella outbreak from contaminated orange juice: supplier
liable, despite absence of negligence. Allens Arthur Robinson, Annual Review of Insurance &
Reinsurance Law 2003 - Duty of care, trade practices and common law liability. Retrieved 15
December 2008, from http://www.aar.com.au/pubs/ari/2003/care.htm#Salmo1
Arnold, G.J. & Coble, J. (1995). Incidence of Listeria species in foods in NSW. Food Australia
47, 71-82.
Baert, K., De Meulenaer, B., Kamala, A., Kasase, C., & Devlieghere, F. (2006). Occurrence of
patulin in organic, conventional and handcrafted apple juice marketed in Belgium. Journal of
Food Protection 69(6), 1371–1378
Bassett, J. & McClure, P. (2008). A risk assessment approach for fresh fruits. Journal of
Applied Microbiology 104, 925-943.
Bennett, C. M., Dalton, C., Beers-Deeble, M., Milazzo, A., Kraa, E., Davos, D., Puech, M., Tan,
A. & Heuzenroeder, M. W. (2003). Fresh garlic: a possible vehicle for Salmonella Virchow.
Epidemiology and Infection 131, 1041-1048
Burda, K. (1992). Incidents of patulin in apple, pear, and mixed fruit products marketed in
NSW. Journal of Food Protection 55, 796-8.
California Food Emergency Response Team (2007), Investigation of an Escherichia coli
O157:H7 outbreak associated with Dole pre-packed spinach. Retrieved 27 November 2008,
from http://www.marlerclark.com/2006_Spinach_Report_Final_01.pdf
Crepet, A., Albert, I., Dervin, C., & Carlin, F. (2007). Estimation of microbial contamination of
food from prevalence and concentration data: application to L. monocytogenes in fresh
vegetables. Applied and Environmental Microbiology, Jan 2007, p. 250-258. Retrieved 4
December 2008, from
http://www.pubmedcentral.nih.gov/picrender.fcgi?artid=1797144&blobtype=pdf
DeWaal, C.S., Tian, Z.A. & Bhuiya, F. (2007). Outbreak Alert! 2008. Closing the gaps in our
Federal food-safety net. Center for Science in the Public Interest.
Doyle, M.P. & Erickson, M.C. (2008). Summer meeting 2007 – the problems with fresh
produce: an overview. Journal of Applied Microbiology 105, 317–330.
Fazekas, Watkins, & Palmer. (1988). Internal report. State Chemistry Laboratory, Victoria,
Australia.
FDA [Food and Drug Administration, US] (Undated), Guide to Inspections of Acidified Food
Manufacturers, . US Food and Drug Administration. Retrieved 14 January 2009, from
http://www.fda.gov/ora/inspect_ref/igs/acidfgde.htm
FDA [Food and Drug Administration, US] (1999). Potential for Infiltration, Survival and
Growth Of Human Pathogens within Fruits and Vegetables. Retrieved 26 Nov 2008, from
http://www.cfsan.fda.gov/~comm/juicback.html
Page 81 of 189
Foodlink (2002). Facilitation and guidance of a risk management process for high risk plant
products (Draft 4). Report for SafeFood Production NSW, Foodlink Management Services,
September 2002.
FSAI [Food Safety Authority of Ireland] (2003). Results of 4th quarter national survey 2002
(NS4), European Commission co-ordinated programme for the official control of foodstuffs for
2002, Bacteriological safety of pre-cut fruit & vegetables, sprouted seeds and unpasteurised
fruit & vegetables juices from processing and retail premises. Retrieved 2 December 2008,
from http://www.fsai.ie/surveillance/food_safety/microbiological/4thQuarter2.pdf
FSA [Food Science Australia] (2000a). Final report – scoping study on the risk of plant
products. Food Science Australia prepared for SafeFood NSW.
FSA [Food Science Australia] (2000b) Fact Sheet Preservation of vegetables in oil and
vinegar. Retrieved 14 January 2009, from http://www.foodscience.afisc.csiro.au/oilvine.htm
FSAI [Food Safety Authority of Ireland] (undated). 3rd Trimester National Microbiological
Survey 2005 (05NS3): EU Coordinated programme 2005, bacteriological safety of prepackaged mixed salads. Food Safety Authority of Ireland, Retrieved 2 December 2008, from
http://www.fsai.ie/surveillance/food_safety/microbiological/mixed_salads.pdf
Food Standards Agency UK (2004). Survey of baby foods for mycotoxins. Retrieved 22
November 2008, from http://www.food.gov.uk/multimedia/pdfs/fsis6804.pdf.
Gilbert, S., Lake, R., Hudson, A & Cressey, P. (2006). Risk profile: Shiga-toxin producing
Escherichia coli in leafy vegetables. Institute of Environmental Science and Research Limited
report prepared for the New Zealand Food Safety Authority. Retrieved 14 January 2009,
http://www.foodsafety.govt.nz/elibrary/industry/Risk_Profile_Shiga_ToxinScience_Research.pdf
Jay, S., Davos, D., Dundas, M., Frankish, E., & Lightfoot, D. (2003). Salmonella in Hocking,
A.D. (Ed.). Foodborne Microorganisms of Public Health Significance (pp. 207-266). Australian
Lake, R., Hudson, A., Cressey, P. & Gilbert, S. (2005). Risk profile: Listeria monocytogenes in
ready-to-eat salads. Institute of Environmental Science and Research Limited report prepared
for the New Zealand Food Safety Authority. Retrieved 14 January 2009, from
http://www.foodsafety.govt.nz/elibrary/industry/Risk_Profile_Listeria_Monocytogenes_ReadyScience_Research.pdf
Little, C.L. & Gillespie, I.A. (2008). Prepared salads and public health. Journal of Applied
Microbiology, Volume 105, (6) 1729-1743. Retrieved 28 November 2008, from
http://www3.interscience.wiley.com/cgi-bin/fulltext/120125069/PDFSTART
Little, C., Taylor, F. & Sagoo, S. (undated). European Commission Co-ordinated Programme
for the Official Control of Foodstuffs for 2005: Bacteriological safety of pre-packaged mixed
salads from retail premises for L. monocytogenes. UK Food Standards Agency, Local
Authorities Co-ordinators of Regulatory Services and the Health Protection Agency. Retrieved
2 December 2008, from
http://www.food.gov.uk/multimedia/pdfs/scwgecsurveymixedsalads.pdf
Mincino, H., Araki, K., Minami, S., Takaya, S., Sakai, N., Miyazaki, M., Ono, A., & Yanagawa,
H. (1999). Massive outbreak of Escherichia coli O157:H7 infection in schoolchildren in Sakai
City, Japan, associated with consumption of white radish sprouts. American Journal of
Epidemiology 120(8), 787-795. Retrieved 27 November 2008, from
http://aje.oxfordjournals.org/cgi/reprint/150/8/797
MMWR [Morbidity and Mortality Weekly] (1998). Outbreak of Cyclosporiasis – Ontario,
Canada, May 1998. Morbidity and Mortality Weekly Report October 2, 1998 / 47(38), 806-9.
Retrieved 27 November 2008, from
http://www.cdc.gov/mmwr/preview/mmwrhtml/00055016.htm
MMWR [Morbidity and Mortality Weekly] (2003). Hepatitis A outbreak associated with green
onions at a restaurant – Monaca, Pennsylvania, 2003. Morbidity and Mortality Weekly Report
Page 82 of 189
November 28, 2003 / 52(47), 1155-1157. Retrieved 27 November 2008, from
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5247a5.htm
MMWR [Morbidity and Mortality Weekly] (2008). Outbreak of Salmonella serotype Saintpaul
infections associated with multiple raw produce items --- United States, 2008. Morbidity and
Mortality Weekly Report August 29, 2008 / 57(34), 929-934. Retrieved 27 November 2008,
from http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5734a1.htm
NSW Health (2000). A cluster of Listeriosis in the Hunter. NSW Public Health Bulletin Vol 11,
No. 3. Retrieved 15 December 2008, from
http://www.publish.csiro.au/?act=view_file&file_id=NB00022.pdf
NSW Food Authority (2008). Report on the microbiological quality of sprouts. NSW Food
Authority. Retrieved 4 December 2008, from
http://www.foodauthority.nsw.gov.au/aboutus/science%2Dand%2Dresearch/evaluating%2D
what%2Dwe%2Ddo/plant%2Dproducts/
O’Brien, S., Mitchell, R., Gillespie, I. & Adak, G. (2000). The microbiological status of readyto-eat fruit and vegetables. A discussion paper prepared for the UK Advisory Committee on
the Microbiological Safety of Food (ACMSF). Retrieved 2 December 2008, from
http://www.food.gov.uk/multimedia/pdfs/ACM476.PDF
OzFoodNet (2006), OzFoodNet: quarterly report, 1 January to 31 March 2006, Communicable
Diseases Intelligence, Volume 30 Number 2 - June 2006. Retrieved 15 December 2008, from
http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-cdi3002-pdfcnt.htm/$FILE/cdi3002f.pdf
OzFoodNet (2006B), OzFoodNet quarterly report, 1 April to 30 June 2006. Communicable
Diseases Intelligence, Volume 26 Issue number 4. Retrieved 14 January 2009, from
http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-2002-cdi2604-pdfcnt.htm/$FILE/cdi2604g.pdf
OzFoodNet (2007), OzFoodNet quarterly report, 1 October to 31 December 2006,
Communicable Diseases Intelligence, Volume 31, Number 1 - March 2007. Retrieved 14
January 2009, from http://www.health.gov.au/internet/main/publishing.nsf/Content/cdacdi3101-pdf-cnt.htm/$FILE/cdi3101j.pdf
Peck, M., Goodburn, K., Betts, R., & Stringer, S. (2008). Assessment of the potential for
growth and neurotoxin formation by non-proteolytic Clostridium botulinum in short shelf-life
commercial foods designed to be stored chilled. Trends in Food Science & Technology 19,
207-216.
Pezzoli, L., Elson, R., Little, C., Yip, H., Fisher, I., Yishai, R., et al (2008). Packed with
Salmonella – Investigation of an international outbreak of Salmonella Senftenberg infection
linked to contamination of prepacked basil in 2007. Foodborne Pathogens and Disease 5(5),
661-668, 2008.
Sivapalasingham, S., Friedman, C.R., Cohen, L. and Tauxe, R.V. (2004). Fresh produce: A
growing cause of outbreaks of foodborne illness in the United States, 1973 through 1997.
Journal of Food Protection 67, 2342-2353.
St. Louis, M., Peck, S., Bowering, D., Morgan, G., Blatherwick, J., Satyen Banerjee, et al
(1988) Botulism from chopped garlic: delayed recognition of a major outbreak. Annals of
Internal Medicine 108, 363-368.
Stafford, R., lMcCall, B., Neill, A., Leon, D., Dorricot, G., Towner, C. & Micalizzi, G. (2002), A
statewide outbreak of Salmonella Bovismorbificans phage type 32 infection in Queensland.
Communicable Diseases Intelligence 26(4) Retrieved 15 December 2008, from
http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-2002-cdi2604-pdfcnt.htm/$FILE/cdi2604k.pdf
Szabo, E., Scurrah, K. & Burrows, J. (2000). Survey for psychrotrophic bacterial pathogens in
minimally processed lettuce. Letters in Applied Microbiology 30, 456-460. Retrieved 3
December 2008, from http://www3.interscience.wiley.com/cgibin/fulltext/119183907/PDFSTART
Page 83 of 189
Szabo, E.A & Coventry, M.J (2001). Vegetables and Vegetable Products. Spoilage of
Processed Foods: Causes and Diagnosis. In Moir, C.J. et al (Eds) Spoilage of Processed Foods
Causes and Diagnosis. Australian Institute of Food Science and Technology, Waterloo.
Victoria DHS (2005). Microbiological survey of freshly squeezed juices from retail businesses
across Victoria. Victorian Government Department of Human Services, Food Safety Unit.
Retrieved 4 December 2008, from
http://www.health.vic.gov.au/foodsafety/downloads/fruit_juice_survey_report_aug05.pdf
WA Health (2006). Doubts about sprouts, environmental health guide. Department of Health
Western Australia. Retrieved 4 December 2008, from
http://www.health.wa.gov.au/envirohealth/food/docs/Doubts_About_Sprouts.pdf
Page 84 of 189
Seafood safety scheme
The food safety hazards of seafood have been extensively studied. Huss, Ababouch
& Gram (2004) considered the management of seafood safety and quality from an
international viewpoint. The risks they identified were based on cases of foodborne
illness traced to seafood and rejections of seafood imports (Table 27).
Table 27 – Summary of international hazard identification studies for seafood
Data analysed
USA, fish, foodborne illness
Hazard
Scombroid
Ciguatera
C. botulinum
USA, molluscan shellfish, foodborne illness
UK, seafood, foodborne illness
USA, seafood, import refusals
EU, seafood, import rejection/detention
Bacterial pathogens
Norovirus (formerly Norwalk-like viruses)
Poisonous fish (puffer fish)
Chemical contaminants
Vibrio spp.
Norovirus
Algal toxin
Bacterial pathogens
Scombroid
Ciguatera
Parasite
Scombroid
Algal toxin
Virus
Bacterial pathogens
Unknown
Bacterial pathogens
Scombroid
Poison
Other
Vibrio spp.
Bacterial pathogens
Hepatitis virus
Algal toxins
Pesticides
Metal contaminants
Antibiotics
Other chemical contaminants
Parasites
adapted from Huss, Ababouch & Gram (2004)
The former SafeFood Production NSW (predecessor organisation of the NSW Food
Authority) commissioned several studies in preparation for the introduction of the
Food Production (Seafood safety scheme regulation) 2001. Subsequent studies have
been undertaken by NSW, South Australian and Australian Governments and by
international agencies. Walsh & Grant (1999) identified hazards as shown in
Table 28.
Page 85 of 189
Table 28 – Hazards in seafood and seafood products
Sector
Hazard
Priority
Wild caught finfish
Histamine/Scombroid 
High
Ciguatera 
Mercury 
Bivalve molluscs
Pathogenic bacteria 
Viruses 
Algal toxins: Paralytic shellfish poisoning (PSP),
Diarrhoetic shellfish poisoning (DSP), Amnesic
shellfish poisoning (ASP), Neurotoxic shellfish
poisoning (NSP) 
Cold smoked fish RTE
Hot smoked fish RTE
Smoked fish vacuum
packed or modified
atmosphere packaged
(MAP)
Listeria monocytogenes 
L. monocytogenes 
Clostridium botulinum 
Bivalve molluscs
Vibrio spp.
Medium
High
Wild caught finfish (raw)
Parasites 
Medium
Bivalve molluscs
Agrichemicals
Aquaculture crustaceans
Vibrio spp. 
C. botulinum
Raw fish – vacuum
packaged or MAP
Surimi RTE
L. monocytogenes
Cooked whole prawns
Post-cooking contamination by pathogenic bacteria
Cooked peeled prawns or
crabmeat
L. monocytogenes, Staphylococcus aureus, general
Salted seafood
S. aureus
pathogens
adapted from Walsh & Grant (1999)
 Those marked were subsequently evaluated by Ross & Sanderson (2000).
Ross & Sanderson (2000) prepared a risk assessment of selected seafood in NSW.
The seafood selected for their study were extracted from the lists developed by
Walsh & Grant (1999). The report noted that the incidence of foodborne illness due
to most hazards was low, but recognised that oysters and other shellfish have
repeatedly been involved in outbreaks. Ciguatera and histamine poisonings are also
relatively common, but are generally less severe in their outcomes (Ross &
Sanderson, 2000).
On behalf of SafeFood Production NSW, Woods & Ruello (2000) facilitated five
industry Sector Working Groups (SWG) to examine the food safety hazards
associated with the five high priority seafood sectors shown in Table 28, and to
recommend practical risk mitigation measures.
Page 86 of 189
Ross, Walsh & Lewis (2002) studied the food safety risks associated with cold
smoking and marination processes used by Australian businesses. This report
identified and ranked hazards with L. monocytogenes, C. botulinum, scombroid and
parasites identified as most significant.
Sumner (2002) undertook a risk profile on seafood and aquaculture products in
South Australia, and based on outbreak data and recalls the report identified
ciguatera, scombroid, viruses, bacterial pathogens and algal toxins as the hazards of
concern.
During development of Standard 4.2.1 – Primary Production and Processing Standard
for Seafood, to underpin the standard A Risk Ranking of Seafood in Australia was
prepared (FSANZ, 2005). The report identifies hazards along the seafood supply
chain and also includes details on imported food testing failures and epidemiological
data. The identified hazards were consistent with those mentioned in other risk
assessment work. Some detailed description on the nature of the hazards is included
below:
Bivalve molluscs (oysters, pipis, mussels)
Bivalve molluscan shellfish are filter feeders, extracting marine algae, bacteria and
nutrients from surrounding waters. Because of this they are prone to contamination
from the growing environment. Some pathogenic bacteria, especially Vibrio spp. are
endogenous to aquatic environments and can survive and grow in oysters,
presenting a risk to health if ingested.
Bacterial pathogens may also be introduced into shellfish growing areas through
pollution from sewage and animal waste. These organisms can multiply quickly,
particularly at higher temperatures, potentially rendering oysters unsafe. Pathogenic
viruses, such as norovirus may be introduced into shellfish growing waters through
sewage pollution and can survive for long periods in shellfish.
Oysters can extract chemical contaminants from their growing waters and
bioaccumulate them to hazardous concentrations in their flesh. Certain species of
toxin-producing algae present a food safety risk from shellfish consumption. Toxins
can accumulate to high levels in shellfish especially, particularly during periods of an
algal bloom.
Prawns – wild caught
Prawns are also potentially exposed to a range of indigenous microbial contaminants
from the water environment. Vibrios are known to utilise the chitinous exoskeleton of
crustacea as points of attachment and to metabolise it as a carbon/energy source
(Karunasagar et al, 1986). V. parahaemolyticus, V. vulnificus and V. cholerae are
considered part of the indigenous microflora of estuarine prawns. V. cholera may be
introduced by human excreta or from aquatic environments where it is
autochthonous. Enteric pathogens derived from faecal contamination may become
established as environmental contaminants in water from which prawns are
harvested and have the potential to contaminate free-living prawns prior to catch.
During on-board processing, dipping of prawns in metabisulphite to inhibit formation
of blackspot can present a risk to asthmatics. Prawns may also be exposed to
chemical hazards from the environment, including the metals arsenic and mercury.
Other chemical residues may be present in wild-catch crustacea due to industrial
pollution and agricultural run-off. This will be a greater risk in estuarine prawns than
those caught in open marine waters (Ross & Sanderson, 2000).
Page 87 of 189
Processing of prawns can lead to the potential for contamination with marine
pathogenic bacteria, other pathogenic bacteria or chemical contaminants. Cooked
prawns can be subject to cross contamination between raw and cooked prawns.
Finfish
At the point of harvest, hazards potentially present in finfish include metals (eg
arsenic and mercury) and indigenous pathogens from the marine or estuarine
environment which are naturally present in live fish. Marine toxins such as ciguatoxin
may be a significant hazard in tropical reef fish. Ciguatoxin is heat stable, and is not
inactivated by normal cooking. Histamine/scombroid is a hazard in certain species of
fish, particularly if the fish are harvested from warmer waters, die before landing or
are subject to time/temperature abuse after landing. Histamine is heat stable.
A number of parasites may be associated with fish species harvested from particular
locations. This is particularly significant for finfish sourced from overseas locations
and that have been associated with illness in humans after ingestion of raw or
undercooked fish. C. botulinum (type E non-proteolytic strains), which causes
botulism, is commonly associated with the marine environment. As spores tend to be
associated with the gut of the fish, evisceration will reduce the risk of exposure.
Other strains may also be present in the processing environment. Cold smoked fish
have a number of significant hazards. Processing temperatures are too low to ensure
freedom from pathogens or parasites. L. monocytogenes may occur post-harvest and
during processing and prolonged storage may allow numbers to increase.
With sushi, the primary concern is related to product prepared in advance and stored
without refrigeration. Hazards include vibrios, other bacterial pathogens and viruses.
Sashimi hazards of concern are parasites and V. parahaemolyticus.
Exposure assessment
Consumption of seafood
Production data for seafood in Australia is summarised in Table 29. From these
figures, the estimated annual consumption of seafood in Australia is about 396,000
tonnes or 18–19 kg per person. This equates to about 10kg of edible weight when
the conversion factor used by Walsh & Grant (1999) is applied. The Fisheries
Research and Development Corporation (FRDC, 2002) estimated the yearly per
capita seafood consumption, expressed as edible weight, to be 15.1 kg in Sydney
and 14.7 kg in Perth. Data on the consumption of fish and seafood products by sex
and age from the National Nutrition Survey (ABS, 1995) is shown in Table 30. This
data showed that seafood was consumed by approximately 20% of the population,
with consumption levels varying between different age groups.
Table 29 – Production volumes for seafood in Australia and NSW 2006–07
Sector
Australia
Tonnes (gross)
NSW
Value ($000)
Tonnes (gross)
Value ($000)
Wild caught
185,925
1,429,328
15,462
80,657
Aquaculture
59,663
793,039
5200
45,975
Seafood imports
198,602
1,184,394
Seafood exports
48,010
1,157,909
adapted from Australian Fisheries Statistics 2007 (ABARE, 2008)
Page 88 of 189
Prevalence of hazards in seafood
The FSANZ (2005) risk ranking report includes statistics on failed tests for seafood
tested upon entry to Australia. These are summarised in Table 31. In addition,
information from FSANZ (2005) on Australian and international surveys of seafood
used to rank risk is included in Table 32.
A sampling program undertaken by the NSW Food Authority from 2004 to 2007
tested 658 samples spanning 60 species to gauge the extent of exposure to mercury
from NSW retail seafood (NSW Food Authority, unpublished). The higher level results
summarised in Table 33 do not necessarily imply noncompliance with Standard 1.4.1
– Contaminants and Natural toxicants of the Food Standards Code. The Maximum
level (ML) is applicable to the mean of results for a prescribed number of sampling
units (determined by the size of the sample lot). Overall 85% of individual samples
were below the appropriate ML but the results suggest that limiting intake of some
fish types remains a valid risk management strategy.
Listeria m onocytogenes in smoked fish
The UK Food Standards Agency recently surveyed L. monocytogenes in smoked fish
(UKFSA, 2008) and the results are summarised in Table 34. Detection of Listeria and
L. monocytogenes were relatively common in cold smoked fish. Detections were less
common in hot smoked fish but L. monocytogenes at levels greater than 100 cfu/g
were only found in hot smoked fish. These results are consistent with Ross &
Sanderson (2000) who reported that cold smoked fish were more prone to
contamination by L. monocytogenes but, due to lower levels of background flora,
there is potential for growth to higher numbers in hot smoked fish.
Page 89 of 189
Table 30 – Consumption of fish and seafood products in Australia
Sex
Age
Male
Male
Male
Male
Male
Male
Male
Male
Male
Female
Female
Female
Female
Female
Female
Female
Female
Female
2–3
4–7
8–11
12–15
16–18
19–24
25–44
45–64
65+
2–3
4–7
8–11
12–-15
16–18
19–24
25–44
45–64
65+
consuming fish and seafood
products and dishes 17
(%)
9.6* 18
10.6
11.8
12.8
8.8
16.0
16.6
20.8
20.3
13.3
16.8
11.5
11.2
16.7
15.8
17.2
20.5
18.8
consumers of fish and seafood
products and dishes
(g/day)
63.3*
71.0
100.5
148.0
114.8*
134.6
120.0
120.0
95.2
47.5*
48.0
90.4
105.0
95.0
99.0
86.3
96.0
74.5
Table 31 – Failure rate for imported seafood products (1998 – 2003)
Commodity
Molluscs
Hazard
Mercury
Crustacea
Standard plate count
Sulphur dioxide
Finfish
Staphylococcal enterotoxins
Standard plate count
Chloramphenicol
Antibiotics
Mercury
Salmonella
V. cholerae
E. coli
L. monocytogenes
Salmonella
V. cholerae
E. coli
L. monocytogenes
Scombroid/Histamine
E. coli
Standard Plate Count
Failure rate (%)
1.0
0.5
0.2 (Oysters 1.0)
2.4 (Oysters 4.8)
0.8
3.5
1.9
0.8
1.3
0.9
0.3
5.4
5.3
5.9
1.3
15.1
1.6
6.5
1.7
adapted from Imported Foods Inspection Scheme data (FSANZ, 2005)
17
Fish and
-
seafood products and dishes are defined in the National Nutrition Survey (ABS, 1995) as including:
Fin fish (excluding canned)
Crustacea and molluscs (excluding canned)
Other sea and freshwater foods
Packed (canned and bottled) fish and seafood
Fish and seafood products
- Mixed dishes with fish or seafood as the major component
18
Results marked with * had a relative standard error of 25 – 50% due to small sample size
Page 90 of 189
Table 32 – Summary of Australian seafood testing results
Hazard
V. parahaemolyticus
V. vulnificus
L. monocytogenes
Commodity
Marine fish at market
Unopened oysters
Opened oysters
Pacific oysters
Scallops, mussels, oysters,
fish
Oysters
Smoked salmon fillets &
slices
Salmon pâté
Smoked fish and mussels
Marina mix
Smoked fish
Seafood salad
Flake
Smoked salmon* 19
Other smoked fish*
Salmon cheese*
Salmon dip*
Salmon mousse/ pâté*
Cooked prawns
Retail seafood
Smoked fish
Dried fish
Detected/Sampled
39/66 (59%)
16/16 (100%)
13/14 (93%)
(69-74%)
20/80 (25%)
Detected at low numbers
1/285 (0.4%) 2/433 (0.4%)
8/61 (29.5%) sic
2/49 (4.1%)
(31%)
(10%)
(3%)
(1.5%)
10/56 (17.9%)
0/11
3/5 (60%)
10/21 (47.6%)
2/8 (25%)
12/380 (3.2%)
1/11 (9%) <100mg/kg
0/13
3/5 (60%) <100mg/kg
1/5 (20%) 653 mg/kg
Canned fish
1/7 (15%) <100mg/kg
Canned tuna
3/107 (2%) 50-100mg/kg
Several species exceed the regulatory limit – see Table 33
Histamine
Mercury
adapted from (FSANZ, 2005)
Table 33 – Summary of high mercury levels in NSW seafood
Fish type
Angel fish
Flake
Ling
Marlin
Shark
Swordfish
Number of
samples
5
41
5
22
23
37
Maximum (mg/kg) 20
1.002
3.35
1.03
1.682
3.47
4.092
Mean (mg/kg) 21
0.712*
0.880
0.503
0.851
0.690
1.454*
adapted from NSW Food Authority (unpublished)
19
Results marked with * is data is from a NSW retail survey. The report includes international information on
Hepatitis A virus and the parasite Anisakis simplex
20
Results for individual samples exceed the maximum level (ML) specified in Standard 1.4.1 – Contaminants and
Natural toxicants of the Food Standards Code
21
Results marked with *, the mean exceeds the ML specified by Standard 1.4.1 – Contaminants and Natural
toxicants of the Food Standards Code, which is generally 0.5 mg/kg for most fish and 1mg/kg for some fish, rays
and sharks
Page 91 of 189
Table 34 – Prevalence of L. m onocytogenes in UK retail smoked fish
Number of samples
Listeria spp. detected
L. monocytogenes detected
L. monocytogenes > 100cfu/g
Cold smoked fish
1,344
282 (20.5%)
236 (17.4%)
0
Hot smoked fish
1,878
96 (5.2%)
66 (3.4%)
3 (0.06%)
adapted from UKFSA (2008)
Algal biotoxins
The Shellfish program of the NSW Food Authority averaged 15–16 oyster harvest
areas closures each year attributable to biotoxin issues from July 2004 to June 2008
(unpublished data). The closures were based on either very high levels of potentially
toxic phytoplankton or positive results from screening tests for algal biotoxins.
The NSW pipi industry also experiences closures due to potential biotoxin issues,
typically in summer or early autumn. Six biotoxin closures were recorded for the
period July 2007 to June 2008. Pipi biotoxin management plans were introduced
following the 1997 and 1998 diarrhoetic shellfish poisoning (DSP) outbreaks and
there have been no subsequent reports of DSP attributed to NSW pipis.
Fate of hazards
A number of hazards are of additional concern because they are not eradicated by
further processing or cooking. These include:
•
Histamine / scombroid
•
Ciguatera
•
Mercury contamination
•
Algal toxins
•
Clostridium botulinum spores
•
Agrichemicals
•
S. aureus toxin
Certain commodities are of additional concern because they may be consumed
without adequate cooking and bacterial pathogens or viruses, if present, are not
eliminated.
•
Oysters
•
RTE cold smoked and hot smoked fish
•
Fish intended for consumption raw (eg in sushi and sashimi)
•
Cooked prawns and other crustaceans
Page 92 of 189
Foodborne illness outbreaks from seafood
OzFoodNet annual reports for 2002–2006 tabulated 85 foodborne illness outbreaks
attributed to seafood, with 558 people affected and 77 hospitalisations.
Table 35 includes an updated summary of Australian foodborne illness outbreaks
attributed to fish and seafood products from 1995 to 2008, while more details of
these outbreaks are provided in Table 68 of Appendix 3.
Several large food poisoning outbreaks related to consumption of oysters occurred in
NSW:
•
in the mid 1980s there were a series of outbreaks of Norovirus from oysters
harvested from the Georges River, the largest outbreak affected over 2000
people and
•
in 1997, an outbreak of Hepatitis A virus (HAV) from Wallis Lake oysters
affected around 467 people with one death.
It is estimated the cost to the industry from the Wallis Lake outbreak was around
$30 million and this was the catalyst for the introduction of the NSW Shellfish Quality
Assurance Program, the forerunner to the current NSW Shellfish Program operated
by the NSW Food Authority. Prior to 1997, there was some voluntary monitoring by
shellfish farmers, but no consistent testing of water quality in harvest areas. The
implementation of harvest area management plans has gone a long way to
minimising the risk from shellfish (Food Science Australia & Minter Ellison Consulting,
2002).
The National Risk Validation Project highlighted producers, harvesters, processors
and vendors of raw ready-to-eat seafood (including shellfish) as one of five high risk
foods (Food Science Australia & Minter Ellison Consulting, 2002). FSANZ (2005)
reports that 3 outbreaks (with 102 people affected) of shellfish poisoning occurred in
Australia in the period 1990–2000. Mussels with levels of paralytic shellfish poisoning
(PSP) toxin exceeding regulatory limits were detected in Victoria in 1988 and every
year between 1990 and 1995. PSP toxins exceeding regulatory limits have been
reported in Tasmanian mussels, oysters and scallops. Outbreaks of DSP were caused
by NSW pipis in 1997 and 1998. There has been a detection of amnesic shellfish
poisoning (ASP) toxin (domoic acid) above regulatory limits in scallop viscera from
Victoria.
Page 93 of 189
Table 35 – Summary of foodborne illness outbreaks attributed to seafood
Hazard
Ciguatoxin
Scombroid
Norovirus
Salmonella serovars
Wax ester
Hepatitis A
Vibrio spp.
B. cereus
C. perfringens
DSP
Toxin
Unknown
Total
Australian
outbreaks
(1995–2008)
85
32
9
9
6
5
3
2
2
2
2
23
180
Cases
449
126
303
64
72
517
15
41
58
115
11
208
1979
83
17
1
29
0
64
3
0
1
0
0
9
207
0
0
0
0
0
1
0
0
0
0
0
0
0
Ross & Sanderson (2000) prepared detailed risk assessments on 10 hazard/product
pairs. Current national and international data suggests that their selections remain
appropriate. The extracts below are from their report and the FSANZ risk ranking.
Viral contamination of shellfish
Enteric viruses can be introduced into aquatic environments through contamination
with sewage. They may persist longer than enteric bacteria in marine environments
and can be accumulated in bivalve molluscs. As a consequence, their presence in
shellfish does not always correlate with bacterial indicators of faecal pollution in
marine environments. Viruses may also take longer to depurate from contaminated
shellfish than enteric bacteria and viruses are more resistant to inactivation during
cooking than bacteria. Outbreaks of viral food poisoning associated with shellfish
continue to occur in Australia and worldwide. In general, the incidence of seafoodborne viral food poisoning is low, suggesting that existing control strategies are
effective. Australian outbreaks have been associated with failures or nonimplementation of control strategies.
Noroviruses cause human gastrointestinal illness. Symptoms in children are generally
mild and self-limiting. A more severe gastroenteritis with dehydration as the result of
vomiting or diarrhoea may occur. Mortality in the absence of other compromising
factors is extremely rare. Infections in adults typically manifest as explosive projectile
vomiting and/or diarrhoea. Incubation times are dose dependant, typically 15–50
hours with a mean of 24–48 hours (Ross & Sanderson, 2000).
Hepatitis A (HAV) is usually a mild illness characterised by sudden onset of fever,
malaise, nausea, anorexia and abdominal discomfort followed in several days by
jaundice. The incubation period for HAV varies from 10 to 50 days (mean 30 days),
and is dependent upon the number of infectious particles consumed. Many infections
with HAV do not result in clinical illness, especially in children. When illness does
occur, it is usually mild and recovery is complete in one or two weeks. Occasionally
the symptoms are severe and convalescence can take several months. Patients suffer
from chronic tiredness during convalescence, and their inability to work can cause
financial loss. Less than 0.4% of the reported cases in the U.S. are fatal. These rare
deaths are usually in the elderly (Ross & Sanderson, 2000).
Page 94 of 189
Algal toxins in shellfish
Shellfish poisoning is caused by a group of toxins elaborated by planktonic algae
upon which the shellfish feed. The toxins are accumulated and sometimes
metabolised by the shellfish. Since shellfish toxins are heat stable, the form in which
shellfish are consumed does not affect the level of the hazard. All individuals are
susceptible to shellfish toxins, although the elderly may be more severely affected,
particularly by amnesic shellfish poisoning (ASP).
There are about 20 toxins responsible for PSP, and all are chemical derivatives of
saxitoxin, but differ in the type and localisation of the derivation. PSP toxins are also
produced by species of cyanobacteria found in Australian freshwater rivers and lakes
(Hallegraeff, 2003).
PSP toxins block the sodium channels of excitable membranes of the nervous system
and associated muscles. The extreme potency of PSP toxins has, in the past, resulted
in an unusually high mortality rate. In humans, 120–180 µg of PSP toxin can produce
moderate symptoms; 400–1060 µg can cause death, but 2000–10,000 µg is more
likely to constitute a fatal dose.
DSP is caused by a group of high molecular weight polyethers, including okadaic
acid, the pectenotoxins and yessotoxin produced by the armoured dinoflagellate
algae including Dinophysis spp. and Prorocentrum spp. These species are
omnipresent but their toxicity is variable and unpredictable. Dense blooms can
sometimes be completely non-toxic, but at other times shellfish can become toxic
even when only sparse dinoflagellate populations are present.
No human fatalities have been reported due to DSP and patients usually recover
within three days. Recovery is generally complete with no after effects and the
poisoning is generally not life threatening. In extreme cases chronic exposure may
promote tumour formation in the digestive system.
ASP is caused by the unusual amino acid, domoic acid, produced by chain-forming
diatoms of the Pseudonitzschia spp. The toxicosis is particularly serious in elderly
patients. All fatalities (up to a report date of 2003) had involved elderly patients.
During an outbreak in Canada, the affected people had consumed mussels
containing 300–1200 µg/g of domoic acid.
Vibrio parahaem olyticus in molluscs and crustaceans
Illness is caused when the ingested organism attaches itself to an individual’s small
intestines and secrets a toxin. Not all strains of the organism are pathogenic. There
appears to be a lack of correlation between pathogenicity and serotype of
V. parahaemolyticus isolates. Virulence correlates with the ability to produce a
thermostable direct haemolysin termed the Kanagawa Phenomenon (KP) haemolysin.
KP negative strains appear to be non-pathogenic (Sanyal & Sen, 1974).
Human volunteer studies have established an infectious dose for KP positive strains
between 2 x 105 and 3 x 107 cfu. V. parahaemolyticus can multiply rapidly in seafood
at permissive temperatures. In a study numbers of V. parahaemolyticus on octopus
stored at 30°C increased from 102/g to 108/g in six hours.
Listeria m onocytogenes in RTE smoked fish products.
Indications of the nature of foodborne listeriosis have emerged from outbreak data,
animal studies and mathematical modelling of illness. Knowledge is incomplete
because of difficulties such as: some strains of L. monocytogenes are pathogenic but
others are not; the determinants of pathogenicity are not well understood and so the
distribution of pathogenic strains in food is not known.
Page 95 of 189
However, there is general acceptance of some elements of the disease process (Ross
& Sanderson, 2000):
•
The infectious dose of L. monocytogenes cannot be stated with precision but
it appears that human listeriosis does not usually occur in the absence of a
predisposing risk factor (such as compromised immunity)
•
Most commentators consider doses of <1000 organisms are highly unlikely to
cause illness in normal individuals, and this has been reflected in food safety
regulations
•
Attempts to link exposure to the organism to observed levels of illness
suggest the infective dose is much higher than 1000 organisms, but it
appears in some cases fewer than 1000 organism may cause illness
•
This difference between observed and predicted cases of illness suggests that
the human population susceptible to listeriosis is actually a much smaller subgroup of the immunocompromised population. However, it could also be an
artefact of under-reporting of listeriosis cases, due to some cases only
developing mild flu-like symptoms.
Clostridium botulinum in vacuum-packed RTE fish products
Foodborne botulism results from eating food contaminated with preformed botulinum
toxin due to the presence and growth of Clostridium botulinum bacteria. Botulism
varies from a mild illness to an acute disease which can be fatal. With treatment,
death due to respiratory failure or airway obstruction is rare. The case fatality rate in
North America has fallen from 60% to 20% due to the availability and prompt
administration of antitoxin. Provision of artificial respiration greatly increases the
chances of recovery from intoxication. Nonetheless, recovery may take many
months.
Internationally, the aquatic environment of fish is frequently contaminated with
C. botulinum spores and so fish will often be contaminated also. The organism only
grows in the absence of air, and represents a risk only in those products which
exclude oxygen by virtue of their packaging (eg vacuum packaged, MAP) or contain
anaerobic regions (eg gut left intact). The toxin is heat labile, so the hazard is
primarily limited to RTE seafoods that are stored in vacuum or anaerobic packaging.
For seafoods, botulism is most commonly associated with C. botulinum type E. This
type is capable of growth and toxin production at refrigeration temperatures but
generally needs weeks of growth to produce amounts of toxin to cause foodborne
illness. This is significantly greater than the shelf life generally observed for seafood
and seafood products. Botulism is a concern in extended shelf life products and thus
the concern with vacuum packaging and canning.
Ciguatera poisoning
Ciguatera is a form of human poisoning caused by the consumption of subtropical
and tropical marine finfish which have accumulated naturally occurring toxins
through their diet. In the US, ciguatera intoxication is considered to be one of the
two most common sources of seafood-borne food poisoning associated with finfish.
Human populations of tropical and subtropical marine regions have a much higher
incidence of ciguatera intoxication.
A relatively high incidence of ciguatera poisoning has been reported in Queensland.
Only a small volume of reef fish from Queensland or other problem areas is on sale
in NSW. There have been several large scale outbreaks in NSW involving scores of
victims. The true incidence of ciguatera poisoning in NSW is unknown. The illness
Page 96 of 189
has only recently become known to the general medical community and there is a
concern that the incidence is largely under-reported because of the general non-fatal
nature and short duration.
The ciguatoxins are lipid-soluble toxins that are relatively inert molecules and remain
toxic after cooking and exposure to mild acidic and basic conditions. The minimum
toxic dose is estimated to be about 1ng/kg body weight. In one incident, six US
soldiers became ill after eating fish containing approximately 20ng ciguatoxin/g flesh.
Scombroid / Histamine poisoning
Scombroid poisoning (histamine poisoning) is associated with the ingestion of foods
that contain high concentrations of histamine and possibly other vasoactive amines
and compounds. Histamine is the physiological amine involved in allergic reactions
and is the main toxin involved in histamine fish poisoning. A ‘missing factor’ might be
required to produce illness.
Due to uncertainty about its aetiology, it is difficult to determine the susceptible
population for scombroid poisoning. A wide range of histamine concentrations in
implicated foods, particularly the increasing number of incidents associated with low
histamine concentrations, suggests that some individuals are more susceptible to the
toxin than others. Symptoms can be severe for the elderly and for those taking
medications such as isoniazid, a potent histamine inhibitor.
Mercury in seafood
The commentary provided by Ross & Sanderson (2000) on mercury in NSW seafood
has not lost currency.
“Based on acute mercury food poisonings in Japan and Iraq, it is known that high
levels of dietary mercury may cause measurable deficits in mental and physical
development of young children exposed during gestation. Low levels of mercury are
naturally present in the environment and in all foods. Inorganic mercury is poorly
absorbed via the diet, however, in aquatic environments bacteria can convert
inorganic mercury to methylmercury (MeHg) which is readily absorbed by the human
body. MeHg is bioaccumulated in aquatic food chains, so all fish contain small
amounts of mercury in their muscle tissue. Predatory fish or mammals such as
whales at the top of the food web have the highest amounts. Mercury levels in most
commercially harvested oceanic fish in the US and Australia are <0.5 mg/kg MeHg,
but some large predators such as sharks, marlin and swordfish may have higher
levels. Numerous studies have shown that nearly all the human exposure to MeHg
occurs via seafood (predominately finfish) consumption. Therefore individuals who
regularly consume large amounts of fish (particularly those fish with high mercury
levels) could be exposed to dangerous levels of mercury.”
Corbett & Poon (2008) reported on cases in NSW where elevated mercury levels
were found in three infants, who had eaten fish congee (a rice and fish porridge) as
a weaning food and ate fish regularly as toddlers. The parents had sought medical
advice as a result of the children displaying either developmental delay or
neurological symptoms. Fish congee is a common weaning food in coastal regions of
southern China and South-East Asia. The authors recommended the development of
multilingual information about fish and mercury be made available to pregnant
women and mothers, especially targeting groups who are likely to be frequent
consumers of fish and who use fish in weaning and infant foods.
Page 97 of 189
Viral contamination of shellfish
There is very little information on levels of enteric viruses in shellfish available on
which to base a risk characterisation. The greatest uncertainties in assessing the risk
are the levels of the viruses of concern (HAV and norovirus) in contaminated
shellfish, the frequency of shellfish contamination and the rate of loss of infectivity of
the viruses in the environment and the oyster (Ross & Sanderson, 2000).
FSANZ concluded that the overall public health risk for bivalve molluscs is relatively
high for products harvested in polluted waters and/or waters not subject to a
monitoring scheme such as the Australian Shellfish Quality Assurance Program
(ASQAP). The relative risk ranking is not significantly reduced where these products
are lightly cooked or steamed prior to consumption (FSANZ, 2005).
Where the implementation of shellfish safety management schemes, such as ASQAP,
is taken into account, the relative risk ranking for oysters and other bivalves is
reduced to medium. The Seafood safety scheme requires shellfish harvesters to
comply with the harvest area management plans developed by the NSW Food
Authority. These plans are established to ensure compliance with ASQAP
requirements.
Algal toxins in shellfish
Ross & Sanderson (2000) assessed the risk of algal biotoxins as low from commercial
harvest areas and medium from recreational harvest areas. The difference was due
to the algal monitoring and area management that occurs in commercial harvest
areas.
FSANZ found the relative risk is medium for waters that are subject to pollution, but
where harvesting of shellfish is controlled under an effective management system.
The risk rating is elevated to high if there is no effective management system in
place (FSANZ, 2005).
Vibrio parahaem olyticus in molluscs and crustaceans
Levels of V. parahaemolyticus in Australian seafood are similar to that found in other
parts of the world. It has been estimated that a meal of raw shellfish would contain
no more than 104 cfu KP positive cells, based on typical numbers of
V. parahaemolyticus present in fish and shellfish and the low incidence of KP positive
isolates in the marine environment. For an infectious dose to be reached,
mishandling of food at temperatures allowing the growth of the bacterium would be
required.
As Vibrio spp. are sensitive to heat, it is raw or inadequately cooked product that
poses the greatest risk of vibriosis. However, several documented cases have
involved post processing contamination. The rapid growth rate of the organism at
ambient temperatures exacerbates the consequences of post-processing
contamination.
Although pathogenic Vibrio spp. are often found in bivalve molluscs and on
crustaceans, the incidence of illness is low. For healthy individuals, doses of
organisms higher than those normally found on food are required. The risk of
contamination is seasonal, corresponding to the increased levels of Vibrio spp. in
growing areas as water temperatures rise. The risk of thermal abuse also increases
during summer.
Page 98 of 189
The FSANZ relative risk ranking for V. parahaemolyticus is low but V. vulnificus and
V. cholerae are rated medium based on severity of illness. Foodborne V. vulnificus
infection is clearly associated with underlying medical conditions. Liver disease is a
prominent risk factor for V. vulnificus infection, including cirrhosis due to alcohol
consumption. Additional risk factors include diabetes, gastrointestinal disorders
(surgery, ulcers), haematological conditions, and immunodeficiency due to
underlying conditions such as cancer (WHO/FAO, 2005). The ranking for
V. parahaemolyticus might change if the pandemic O3:K6 strain naturalises in
Australian waters.
Listeria m onocytogenes in RTE smoked fish products
Based on models developed overseas Ross & Sanderson (2000) estimated that 6–7
cases of listeriosis in NSW per annum would be attributable to smoked salmon. This
estimate is about the same order of magnitude as the overall level of incidence
observed from all potential avenues of exposure. The estimate was noted to be
conservative because Australian regulations are tighter than those countries on
which the models were based. Their revised estimate was, at most, a few cases of
listeriosis from smoked vacuum packed seafood per annum in NSW. The outcome of
the FDA/USDA (2003) risk assessment for L. monocytogenes predicted cases of
listeriosis from RTE seafood products to occur very rarely (Table 36). However, the
risk per serving for cooked RTE crustaceans was considered high.
Table 36 – Risk ranking for seafood products contaminated with Listeria
m onocytogenes
Plant product
Cooked RTE
crustaceans
Smoked
seafood
Raw seafood
Preserved fish
Risk
ranking
(per
serve)
High
Predicted cases of
listeriosis per serve
(in Australia) 22
5.1 x 10-9
Risk
ranking
(per
annum)
Moderate
Predicted annual
number of
listeriosis cases
(in Australia) 23
0.2
High
6.2 x 10-9
Moderate
0.1
Low
Low
2.0 x 10-11
2.3 x 10-11
Low
Low
0
0
Ross & Sanderson (2000) then estimated the likely affect of a single, high
contamination event. Depending on the assumptions used for different scenarios, a
single batch of contaminated product was predicted to impact <1, about 20 or 65
immunocompromised consumers.
FSANZ found that contamination of cold smoked products with L. monocytogenes at
levels representing a health risk to the general population is considered unlikely. This
rose to ‘likely’ where there is insufficient management of risk through the food chain
and for susceptible sub-populations. This rises further to ‘very likely’ when both
conditions apply.
22
23
patterns for these foods are identical in Australia and the USA
Page 99 of 189
Other than scrupulous factory hygiene, there is no CCP available to prevent
contamination of RTE cold smoked seafood products. Hot smoking can reduce the
levels of L. monocytogenes on the product, but post-processing contamination can
occur. It appears that some factories are able to achieve very low levels of
contamination relatively consistently, but others are not and rapidly become
recolonised.
Clostridium botulinum in vacuum-packed RTE fish products
On the basis of the low incidence of spores in products likely to be available in the
Australian market, and in particular the typical salt levels in these products, type E
botulism risk from these products is considered to be negligible. Product shelf lives
also mitigate against the risk of sufficient growth of C. botulinum potentially present
to reach toxic doses. Ross & Sanderson (2000) note that other products (including
those with the gut intact) and products from other regions (where C. botulinum
spores could be more frequent) may represent a greater risk.
FSANZ (2005) ascribes a medium relative risk rating for C. botulinum in smoked fish
products. This reflects the balance between severity (severe) and likelihood
(unlikely).
Ciguatera poisoning
Ciguatoxins are responsible for many outbreaks of foodborne illnesses due to fish
consumption in Australia. In the period 1995 to June 2002, outbreaks were recorded
in all states except South Australia and Tasmania. Queensland and NSW accounted
for the great majority of outbreaks, reflecting both the linkage of the illness with fish
caught near tropical reefs in Queensland and the role of Sydney as the hub for
marketing seafood on the east coast of Australia. A number of fish species were
involved, with coral trout, queenfish, Spanish mackerel and cod species predominant.
FSANZ (2005) rates the relative risk as medium for tropical fish species (in particular
larger members of particular species from certain fishing areas).
Scombroid / Histamine poisoning
Time-temperature abuse during transport, processing, storage or display will
potentially allow formation of histamine. Scombroid species of fish, which have high
levels of histadine, are more likely to accumulate high concentrations of histamine
under conditions of temperature abuse, but many non-scombroid species have also
been involved in outbreaks of histamine fish poisoning. Data from testing samples at
retail and results from testing imported fish products indicate a low level of histamine
in whole fish and fish fillets available in Australia. However, epidemiological data
shows a significant number of outbreaks in commercial and restaurant settings,
indicating potential problems in the cold chain and resultant time-temperature abuse.
Tuna, blue grenadier and mahi mahi have been identified as species involved in
these outbreaks.
FSANZ allocated a relative risk rating of low, due to a moderate severity of disease
and the probability of occurring as ‘likely’ (FSANZ, 2005).
Mercury in seafood
Ross & Sanderson (2000) approached a risk assessment for mercury in seafood by
calculating the weight of fish required to equal the provisional tolerable weekly intake
(PTWI) of methylmercury for consumers of varying body weights and various
mercury levels. Their tables are reproduced in Table 37, except that the Joint
FAO/WHO Expert Committee on Food Additives (JECFA) Provisional tolerable weekly
intake (PTWI) estimate has been reduced following a review (JECFA, 2004).
Page 100 of 189
Estimates in Table 37 are based on the JECFA PTWI and US EPA reference dose, for
comparison.
Table 37 – Seafood consumption required to reach reference doses for
methylmercury
Mercury
level
mg/kg
Body weight
13 kg
40 kg
60 kg
70 kg
Weekly consumption (g)
required to reach JECFA PTWI of
1.6ug/kg body weight/week
0.15
0.5
1.0
1.5
146
44
22
15
449
135
67
45
674
202
101
67
786
236
118
79
13 kg
40 kg
60 kg
70 kg
Weekly consumption (g) required
to reach to USEPA reference dose
of 0.7ug/kg body weight/week
63
19
10
6
196
59
29
20
295
88
44
29
344
103
52
34
adapted from Ross & Sanderson (2000); JECFA (2004)
Table 37 shows that for non-predatory fish (average mercury level 0.15 mg/kg –
Ross & Sanderson 2000) significant consumption is required to exceed the PTWI.
Average consumption figures quoted above equate to 200–300g of seafood per
week. Consumers who predominately consume predatory fish or those consuming
above average levels of fish are at risk.
JECFA noted the existing PTWI of 1.6 µg/kg body weight was set in 2003 based on
the most sensitive toxicological end-point (developmental neurotoxicity) in the most
susceptible species (humans). However, life-stages other than the embryo and
foetus may be less sensitive to the adverse effects of methylmercury (JECFA, 2006).
In the case of adults, intakes of up to about two times higher than the existing PTWI
of 1.6 µg/kg body weight would not pose any risk of neurotoxicity. Although in the
case of women of childbearing age, the intake should not exceed the PTWI, in order
to protect the embryo and foetus.
JECFA’s data did not allow firm conclusions to be drawn regarding the sensitivity of
infants and children compared to that of adults. While it is clear that they are not
more sensitive than the embryo or foetus, they may be more sensitive than adults
because significant development of the brain continues in infancy and childhood. The
joint committee could not identify a level of intake higher than the existing PTWI that
would not pose a risk of developmental neurotoxicity for infants and children (JECFA,
2006).
Conclusion
The Wallis Lake Hepatitis outbreak in 1997 graphically demonstrated the need for
tighter food safety controls on commercial harvesting of shellfish for human
consumption. Since that time, the implementation of a seafood safety scheme and
the NSW Shellfish Program has significantly improved the safety of shellfish through
the classification of harvest areas and the implementation of harvest area
management plans which identify high risk events such as heavy rainfall and holiday
periods which may contribute to pollution of the waterways and compromise shellfish
safety. As coastal populations continue to increase and place additional pressure on
local infrastructure such as sewage treatment plants, it is considered that the future
role of the NSW Shellfish Program in ensuring the continued safety of shellfish is
vital. This was acknowledged by FSANZ when it ranked shellfish harvested from
managed areas as a medium risk, as opposed to high risk when these controls were
not in place.
Page 101 of 189
The management of other food safety hazards associated with seafood, such as
minimising the risk of histamine poisoning, requires general food safety control
measures such as hygiene and sanitation and the application of appropriate storage
temperatures. The seafood safety scheme requires businesses processing seafood to
implement a food safety program, to ensure appropriate control measures are
implemented for hazards such as L. monocytogenes and C. botulinum.
Because it naturally occurs in seafood, the issue of mercury is addressed through
consumer education campaigns, particularly targeting high risk consumers such as
pregnant women.
Page 102 of 189
References – Seafood
ABARE [Australian Bureau of Agricultural Resource] (2008). Australian Fisheries Statistics
2007. Australian Bureau of Agricultural Resources. Retrieved 30 September 2008, from
http://www.abare.gov.au/publications_html/fisheries/fisheries_08/08_fishstats.pdf
January 2009, from
D460/$File/48040_1995.pdf
Corbett, S.J. & Poon, C.C.S. (2008). Toxic levels of mercury in Chinese infants eating fish
congee. Medical Journal of Australia. 188(1), 59-60.
Food Science Australia & Minter Ellison Consulting (2002). National Risk Validation Project.
Final Report.
FRDC (Fisheries Research and Development Corporation] (2002). Retail Sale and
Consumption of Seafood (Revised Edition). Ruello and Associates for the Fisheries Research
and Development Corporation. Retrieved 14 January 2009, from
http://www.frdc.com.au/bookshop/Seafood_report.pdf
FSANZ (2005). Final Assessment Report, P265, Primary Production and Processing Standard
for Seafood (Attachment 10). Retrieved 3 September 2008, from
http://www.foodstandards.gov.au/_srcfiles/P265_Seafood_PPPS_FAR.pdf#search=%22risk%
20ranking%20seafood%22
Hallegraeff, G.M. (2003). AIFST (2008). Algal toxins in Australian shellfish. In Hocking, A.D.
(Ed.). Foodborne Microorganisms of Public Health Significance (pp. 675-688). Australian
Huss, H.H., Ababouch, L. & Gram, L. Assessment and management of seafood safety and
quality. FAP Fisheries technical Paper 444. Retrieved 30 September 2008, from
ftp://ftp.fao.org/docrep/fao/006/y4743e/y4743e00.pdf
JECFA [Joint FAO/WHO Expert Committee on Food Additives] (2004), WHO Food Additives
Series 52, Safety Evaluation of Certain Additives and Contaminants. Retrieved 21 November
2008, from http://whqlibdoc.who.int/publications/2004/924166052X.pdf
JECFA [Joint FAO/WHO Expert Committee on Food Additives] (2006), Joint FAO/WHO Expert
Committee on Food Additives Summary and Conclusions of the 67th Meeting. Retrieved 21
November 2006, from http://www.who.int/ipcs/food/jecfa/summaries/summary67.pdf
Karunasagar, I, Venugopal, M.N., Karunasagar, I. & Segar, K. (1986). Role of chitin in the
survival of Vibrio parahaemolyticus at different temperatures. Canadian Journal of
Microbiology 32, 889-891.
OzFoodNet (2002 to 2006). Annual Report of the OzFoodNet Network (5 individual annual
reports). Retrieved 30 September 2008, from
http://www.ozfoodnet.org.au/internet/ozfoodnet/publishing.nsf/Content/reports-1
Ross, T. & Sanderson, K. (2000). A Risk Assessment of Selected Seafoods in NSW (Final
report December 2000). SafeFood Production NSW.
Ross, T. Walsh, P. & Lewis, T. (2002). Risk Assessment of Fish Cold Smoking and marination
Processes Used by Australian Businesses. Biodevelopment Consulting Pty. Ltd for SafeFood
Production NSW.
Sanyal, S.C. & Sen, P.C. (1974). Human volunteer study on the pathogenicity of Vibrio
parahaemolyticus. In T. Fujino, G. Sakaguchi, R. Sakazaki, Y. Takeda (Eds) International
Symposium on Vibrio paramhaemoylticus (pp. 227-230) Saikon Publishing Co. Tokyo.
Page 103 of 189
UK Food Standards Agency (2008). A microbiological survey of retail smoked fish with
particular reference to the presence of Listeria monocytogenes, Food Survey Information
sheet 05/08. Retrieved 30 September 2008, from
http://www.food.gov.uk/multimedia/pdfs/fsis0508.pdf
Walsh, P. & Grant, N. (1999). Consultancy for Researching the Business Profile of the NSW
Seafood Industry & Food Safety Hazards of Seafood in NSW (Final Report). Food Factotum.
Nations] (2005). Risk assessment of Vibrio vulnificus in raw oysters. Interpretive summary
and technical report. Microbiological risk assessment series 8. Retrieved from
http://www.who.int/foodsafety/publications/micro/mra8.pdf
Woods, J. & Ruello, N. (2000). Report of Seafood Sector Working Groups’ Development of
Model Food Safety Programs. Ruello and Associates Pty. Ltd. For SafeFood Production NSW.
Page 104 of 189
Vulnerable persons food safety scheme
From time to time certain population subsets within the community are more at risk
to foodborne illness or can develop more serious complications from foodborne
illness than the general population (Acheson & Lubin, 2008). Exactly defining who is
vulnerable can be problematic. This is predominately due to the differing degree of
vulnerability from one person to the next and the varying degrees of virulence of
some pathogenic microorganisms to different vulnerable sub-populations (Acheson &
Lubin, 2008). Acheson & Lubin (2008) provides an overview of the different factors
that influence vulnerability and in general terms vulnerability is due to a suppressed
immune system, either due to age, pregnancy, disease or pharmacologic therapy (ie
chemotherapy or immunosuppressive drug use after an organ transplant). As such it
is common to include the following sub-groups within the vulnerable population
group:
•
Children under 5 years old
•
People over 65 years of age
•
Pregnant women
•
Persons with depressed immunity due to either some underlying condition,
therapy treatment or medication
The increased risk posed by the vulnerable populations requires businesses that
cater specifically to these groups to consider the risk when deciding on the types of
foods and how they prepare, store and serve these foods. In developing Standard
3.3.1 – Food Safety Program for Food Service to Vulnerable Populations of the Food
Standards Code, Food Standards Australia New Zealand (FSANZ) defined the
vulnerable population by considering the types of businesses likely to serve food to
these people (FSANZ, 2006). Standard 3.3.1 of the Food Standards Code (FSANZ,
2008) includes a list of these businesses to which the standard applies, these
include:
•
Hospitals
•
Nursing homes
•
Hospices
•
Certain daycare establishments and
•
Childcare centres
In performing a risk assessment on businesses catering to vulnerable populations, it
is acknowledged that the businesses can supply a variety foods to these groups and
the methods for preparation will vary from complete preparation and assembly within
the business through to purchase of ready-to-eat (RTE) foods. To avoid duplication
this section should be read in conjunction with other sections within this risk
assessment in respect to the risk posed by different foods. Information will be
provided to illustrate areas of concerns and elaborate on other foods not covered in
other sections of this document.
This section will focus on microbiological hazards, only as the risks posed by chemical
and physical hazards are not known to be influenced by a decreased immunity. It
should be noted that most of the risk assessments conducted do not specifically
address establishments serving to vulnerable populations. Where they do examine
specific hazards that affect the vulnerable population (eg L. monocytogenes ) the
context is usually within that of the general population and includes both those
Page 105 of 189
situated in care-type establishments and those living outside these establishments.
Wherever possible, this risk assessment will attempt to focus on the risks associated
with those people within care-type establishments, although due to the lack of
information specific to these establishments this may not always be possible.
When considering the food safety hazard presented to vulnerable populations, the
hazards can be separated into two groups:
•
Specific hazards – those hazards that present a unique risk to vulnerable
populations and
•
General hazards – those hazards that, due to a decrease in immunity of an
individual, can result in a greater prevalence in illness when compared to the
general population or result in more serious illnesses.
General information concerning the hazards included in this section can be found in
Appendix 1.
Specific hazards
It is well documented the importance of controlling L. monocytogenes in foods
consumed by the vulnerable population. While the exact dose needed to cause illness
in the vulnerable populations is ill-defined and open for much debate, it is generally
agreed that lower infective doses are needed for illness to occur within the
vulnerable population. However, the type and severity of illness may be dependent
on virulence of the pathogen, host susceptibility and the food matrix (FDA/USDA,
2003). Sutherland et al. (2003) notes that while the infective dose is not clearly
defined, some studies suggest infective doses as low as 102 to 103 cfu/g may cause
illness.
L. monocytogenes is of concern in any RTE food or foods not likely to receive a heat
treatment prior to consumption. This is predominately due to the organism being
ubiquitous in nature, the potential for cross contamination after cooking and the
ability of the organism to grow at refrigeration temperatures. In their risk
assessment, the FDA/USDA (2003) ranks the potential risk posed by some RTE
foods. Those of very high to high risk include:
•
Deli meats and uncooked frankfurters
•
Pâté and meat spread
•
Unpasteurised milk
•
Smoked seafood
•
High fat and other dairy milk
•
Pasteurised milk
•
Soft unripened cheese
Others which present a low risk include cooked crustacean, salads, fermented
smallgoods, other soft cheese and fruits and vegetables.
In general terms, any foods that can support the growth of L. monocytogenes and
does not include a cook step prior to consumption can potentially present some level
of risk to the vulnerable populations.
Page 106 of 189
Infant botulism has been reported in many countries including Australia. It is caused
by the ingestion of C. botulinum spores which subsequently germinate, multiply and
produce toxin in the infant’s gastrointestinal tract. It usually occurs in infants aged
one year or less. Symptoms include constipation followed by weak sucking and
crying ability. The illness affects the nervous system and while death can occur,
mortality rates are generally low due to good intensive care facilities. In cases of
infant botulism, the cause is often unknown, however the presence of C. botulinum
in honey is thought to be one cause of infant botulism (Szabo & Gibson, 2003).
Cronoobacter. sakazakii, recently reclassified from the genus Enterobacter, is a
pathogenic microorganism that has been linked to foodborne illness outbreaks
predominately affecting infants (Lenhner & Stephan, 2004). While there is limited
surveillance data, FAO (2008) reports at least 120 cases worldwide with 27 deaths.
Powdered infant and follow-on formula have been identified as the main food
vehicle, with practices such as reconstitution with warm water and holding bottles at
room temperature increasing the risk of foodborne illness (FAO, 2007 FAO, 2008).
Other factors thought to increase the risk of illness include: age of the infant,
nutritional status, HIV status, other clinical conditions, pharmaceutical treatment, low
birth weight and premature birth (FAO, 2008). C sakazakii isolates are thought to
have a high rate of antibiotic resistance (Lehner & Stephan, 2004).
Vibrio vulnificus
A specific sub-group within the vulnerable population are at risk from infection by
V. vulnificus that is found in the marine environment and can contaminate seafood.
V. vulnificus infections normally affect people with liver dysfunctions (eg cirrhosis,
hepatitis) and also patients with malignancies or those who have undergone
gastrectomy (ICMSF, 1996). Symptoms of infection from V. vulnificus include fever,
chills and nausea (Desmarchelier, 2003). While infections are rare, mortality rates
are high. Most illnesses have been linked to consumption of raw seafood,
predominately raw oysters (Desmarchelier, 2003).
General hazards
When vulnerable populations are exposed to other pathogenic microorganisms the
resulting illnesses are like to be more prevalent and more severe than in the general
population. Buzby (2002) attributed this in elderly people to age related factors (eg
decreased immune function and stomach acid production, digestive orders,
medication and altered sense of smell and taste) and a decrease in stomach and
intestinal contractions resulting in a longer time required to eliminate pathogens and
allowing a greater time for toxin formation and damage. Buzby (2002) also reports
that in the US, rates of foodborne illness can be 10 to 100 times greater for elderly
people within nursing homes when compared to the general population and that the
elderly are more vulnerable to gastroenteritis-induced deaths.
Other sub-groups within the vulnerable population exhibit increased sensitivity to
foodborne illnesses due to decreased immunity. Acheson & Lubin (2008) contribute
this increased risk due to many factors including the use of antibiotics that, while
they aim to treat illnesses caused by certain pathogens, they can also eliminate from
the intestinal tract certain microorganisms that inhibit or suppress the growth of
pathogenic microorganisms. Cancer and transplant patients also have greater
susceptibility to foodborne illness due to their treatments lowering the immune
Page 107 of 189
system, with mortality rates from foodborne illness higher than the general
population (Acheson & Lubin, 2008).
Jay et al (2003) also suggests that the immunocompromised or those with
underlying disease are at a greater risk of infection from Salmonella and the infection
is likely to result in more serious illness. It is thought that the lower gastric acidity
and immature immune response may influence the sensitivity of children to
salmonellosis (Jay et al, 2003). This appears to be supported by a higher number of
reported salmonellosis infections in children aged four or under, at least three times
higher than other age groups (NSW Health, 2008).
Other pathogens where increased prevalence or severity has been observed in the
vulnerable population include:
•
Enteropathogenic E. coli – strains of shiga toxigenic E. coli (STEC) are known
to cause severe illness in infants and the elderly and can result in death
(Desmarchelier & Fegan, 2003)
•
Staphylococcus aureus – while for the healthy populations staphylococcal
food poisoning is rarely fatal, fatalities have been reported in infants and the
elderly (Stewart, 2003)
•
Clostridium perfringens – fatal cases of C. perfringens food poisoning are
•
generally associated with the elderly in institutionalised settings (Bates &
Bodnaruk, 2003) in the general population fatalities are rare and
Bacillus cereus – fatal cases are very rare, when reported they have been
linked to children with liver failure (Dierick et al, 2005)
Exposure assessment
Estimating the exact portion of the vulnerable population who are in care-type
establishment that provide food, and the number of meals served by these facilities
is difficult, although there is some information that may be used to estimate potential
numbers of both.
Population figures from the Australian Bureau of Statistics surveys (ABS, 2005; ABS,
2008) indicate that in NSW:
•
In June 2008 there were 225,945 children aged 4 years old or younger
•
In 2005 there were 17.5% and 35.8% of children aged 0 to 2 years old and 3
to 4 years old respectively in long daycare
Using these figures it could be assumed that approximately 26.6% of children aged
less than 5 years old are in long daycare, which would correlate to 60,214 children in
long daycare facilities. It should be noted that not all these children would be served
meals prepared by the facility and the number of meals each facility serves may
differ.
A survey conducted by the NSW Food Authority (2008a) indicates that:
•
1,856 childcare centres in NSW provide food for approximately 79,808
children each day
•
Approximately 26,815,488 meals are served in childcare centres each year
ABS data (ABS, 2008) also indicate that in June 2007, there were 422,656 people
aged 65 or older. The NSW Food Authority (2008b) surveyed other businesses
included in the definition of Standard 3.3.1 – Food Safety Program for Food Service
to Vulnerable Populations of the Food Standards Code and found that:
Page 108 of 189
•
there are 1867 facilities in NSW as defined by Standard 3.3.1 (excluding
childcare facilities)
•
these facilities serve approximately 106,824,172 meals each year
Therefore, in total, ’food service to vulnerable populations‘ facilities would serve
approximately 133 million meals per year in NSW. It would be expected that some of
the components of these meals may present a risk to sub-groups within the
vulnerable population.
Foodborne illness outbreaks involving food service establishments for
vulnerable populations
Table 38 provides a summary of foodborne illness outbreaks attributed to food
served to vulnerable persons in Australian institutions (Table 69 of Appendix 3
provides more detailed information on each outbreak). Since 1995 there have been
67 foodborne illness outbreaks across Australia involving establishments that serve
food to vulnerable populations, with 1138 illnesses, 64 hospitalisations and 12
fatalities. These outbreaks occurred in aged-care facilities, childcare centres and
hospitals and the most common organism implicated was Salmonella, others
organisms involved include C. perfringens, L. monocytogenes and Campylobacter.
An outbreak in 1998–99 in aged-care facilities and hospitals in the Hunter Valley,
NSW highlighted the risks of listeriosis from foods served in these establishments.
The implicated food was fruit salad and the outbreak affected 9 patients, with 6
deaths resulting. All patients were elderly, and some had underlying conditions
making them more susceptible to infection with L. monocytogenes. All the
establishments served food prepared in a central catering facility (Food Science
Australia & Minter Ellison Consulting, 2002). One sample of fruit salad subsequently
tested positive for low levels (<50 cfu/g) of L. monocytogenes, a level considered
unlikely to cause illness, even in immunosuppressed individuals.
Table 38 – Summary of foodborne illness outbreaks attributed to food served to
vulnerable persons
Hazard
Salmonella serovars
C. perfringens
Campylobacter spp.
L. monocytogenes
Norovirus
Toxin
Viral
B. cereus
St. aureus
Cryptosporidium
Pathogenic E. coli
Unknown
Total
Australian
outbreaks
(1995–2008)
23
10
7
5
4
3
3
1
1
1
1
8
67
Cases
395
267
101
24
111
44
38
19
7
4
2
126
1138
43
1
6
5
0
1
0
0
0
0
0
8
64
4
1
0
7
0
0
0
0
0
0
0
0
12
Page 109 of 189
Table 39 – Institutional foodborne illness outbreaks as a percentage of all
outbreaks 24
Year
Outbreaks
Cases
Hospitalisation
Deaths
(% of total)
(% of total)
(% of total)
(% of total)
2001
5.8%
2.9%
1.4%
NR 25
2002
8.7%
5.6%
4.8%
50%
2003
15.1%
16.2%
32.4%
66.7%
2004
9.3%
8.1%
24.1%
NR
2005
12.7%
10.3%
6.0%
NR
2006
6.1%
6.4%
24.6%
NR
adapted from outbreak data from OzFoodNet 2002-2006 (OzFoodNet Working Group, 2003; 2004;
2005; 2006; 2007)
Vulnerability to foodborne illness
Previous sections of this chapter provide some insight into the factors why some
groups within the population are more vulnerable to foodborne illness than others.
This can be further illustrated by reviewing foodborne illness surveillance data. Table
39 provides a breakdown on the percentage of outbreaks reported to have occurred
in facilities serving food to the vulnerable populations.
Based on NSW Food Authority research (2008) and ABS data (ABS 2005 ABS 2008a
ABS, 2000b), the percentage of the NSW population within facilities catering to
vulnerable populations is approximately 2.5%. When this is compared to the figures
in Table 39, it can be seen that foodborne illness affecting individuals in facilities
catering to vulnerable populations are over-represented compared to the entire
population which may be an indication of their increased vulnerability.
Prevalence of pathogens
Very little information is available on the prevalence of pathogens or other
microorganisms in foods served to vulnerable populations. Other chapters within this
document provide some general information on the prevalence of microorganisms in
certain commodities some of which would be served to vulnerable populations.
A study conducted by Gillespie et al (2001) in the UK looked at the microbiological
quality of sliced cold RTE meats from catering establishments. They found that 26%
of samples were categorised as unsatisfactory when compared to UK Public Health
Laboratory Services microbiological guidelines, with 0.4% of samples categorised as
unacceptable or potentially hazardous. Gillespie et al (2001) also compared the
results of various food handling practices and found:
•
A higher level of unsatisfactory or unacceptable results with product made
external to the kitchen when compared to product made in-house
•
A higher level of unsatisfactory or unacceptable results with product
purchased pre-sliced when compared to product sliced in-house.
A review of ready-to-use vegetables from health-care facilities found
L. monocytogenes in 5/135 samples (3.7%) and also found total bacterial levels
similar to samples that had been subjected to temperature abuse scenarios
(Odumeru et al, 1997).
24
25
Institutions include aged-care facilities, childcare, hospitals and institutions
NR – not reported
Page 110 of 189
During 2005 and 2006, Little et al (2008) undertook a study on the microbiological
safety of sandwiches served in hospitals and other health care establishments in the
UK. In this study they found L. monocytogenes in 2.7% of 88 samples which
included samples collected from wards. They also found a higher frequency of
L. monocytogenes in sandwiches prepared outside the establishment, where the
filling included poultry meat or contained salad ingredients, soft cheese and/or
mayonnaise.
Food service operations
Food service operations by establishments preparing foods for vulnerable populations
can undertake a variety of methods to prepare these foods. The types of operations
can include:
•
Preparation and plating of raw or RTE foods
•
Preparation and plating of previously cooked foods without further heating
•
Preparation and plating of freshly cooked foods
•
Reheating and plating of foods previously cooked using:
o Cook chill for short shelf life or
o Cook chill for extended shelf life
There are also some other specific operations for certain sub-groups that present
specific hazards and will influence the risk to the vulnerable populations. Examples of
these include:
Visitors to some establishments (eg hospitals, aged-care facilities) bringing
food to patients or residents, some of which can present a risk to the subpopulation (Wall, 2008)
• Texture-modified or puréed foods provide the opportunity for recontamination
of cooked foods due to improperly cleaned and sanitised equipment (Tallis et
al, 1999)
• Extended storage and handling of reconstituted infant formula can increase
the risk of foodborne illness in infants due to C. sakazakii (Lehner & Stephan,
2004)
In addition to these operations, food establishments may also purchase some foods
or meals ready cooked, which then require little or minimal handling by the
establishment.
•
The hazard and subsequent risks associated with the foods served to the vulnerable
populations will be influenced by the type of operations they undertake. For
example:
•
•
•
•
Inadequate control of the cook chill process (eg poor cooling rates, improper
storage temperatures and inadequate reheating) can result in the growth and
survival of pathogenic microorganisms (Cox & Bauler, 2008)
Improper storage time and temperature of RTE foods that require no further
heat treatment can result in the growth of L. monocytogenes (ILSI, 2005)
Inadequate cooking and poor post-cooking temperature growth can result in
the survival and subsequent growth of pathogenic microorganisms (Cox &
Bauler, 2008)
For foods served raw, inadequate control steps to minimise the presence of
pathogenic microorganisms and inhibit their growth during storage
(Desmarchelier & Fegan, 2003; Sutherland et al, 2003)
Page 111 of 189
Risk of listeriosis
The high risk associated with listeriosis in establishments serving foods to the
vulnerable population has also been noted in the National Risk Validation Project
(Food Science Australia & Minter Ellison Consulting, 2002). In this report the authors
ranked L. monocytogenes and foodservice operations for sensitive populations as the
highest risk rating due to the ability of the pathogen to grow at refrigeration
temperatures and the high mortality and hospitalisation rates associated with the
listeriosis infection.
The main hazard affecting the vulnerable population that has been studied is
L. monocytogenes. FAO (2004) published a risk assessment on L. monocytogenes in
RTE foods that assessed the relative susceptibility of different groups within the
population to listeriosis (Table 40). From this table it can be seen that the subgroups within the vulnerable population are more susceptible to listeriosis and in turn
the food served to them presents a greater risk of foodborne illness than the food
consumed by the general population.
In their risk assessment on L. monocytogenes in RTE foods, the FDA/USDA (2003)
estimated the number of cases of listeriosis per serving and per annum for different
food categories for certain sub-groups of the vulnerable population. Assuming similar
consumption rates in Australia and using Australian population figures, the potential
number of listeriosis cases per year within Australia for each food category can be
estimated (Table 41). It can be seen from this data that the risk of contracting
listeriosis from any single serving of food is extremely rare, even for the highest risk
foods (eg deli meats, estimated cases are 3.0 x 10-7 per serve for the elderly,
therefore 30 million serves of deli meats would result in one case of listeriosis each
year).
Taking this estimation of risk, and extrapolating from the FDA/USDA (2003) data for
all elderly consumers (not only those residing in aged care facilities), the number of
serves of deli meats in Australia each year may actually result in up to 70 cases of
listeriosis (Table 41). However, the number of elderly actually exposed to
L. monocytogenes is likely to be much lower in aged care facilities. Even if deli meats
were served at every meal in aged care facilities, the number of meals (estimated at
106 million per year) means that the estimated number of cases of listeriosis is likely
to be less than 3.5 per annum.
Risk of foodborne illness associated with C. perfringens
A risk profile published by Meat and Livestock Australia (2003) examined the risk
posed by C. perfringens in institutional meals for the aged where food safety
programs have been implemented. In determining the risk, factors such as severity,
probability, and the effect of processing and handling were considered. From this
information it was concluded that the risk rating of C. perfringens in institutional
meals for the aged was high with an estimated of 250 cases of C. perfringens
foodborne illness in Australia per year. The ABS (2008) estimates that 33.8% of the
population aged over 65 reside in NSW. Assuming the proportion of elderly within
aged-care facilities is similar, it can be estimated that the number of cases of
foodborne illness due to C. perfringens in facilities in NSW would be 84.5 per annum.
Page 112 of 189
Table 40 – Relative susceptibility to listeriosis for different sub-groups
Condition
Transplant
Cancer – blood
AIDS
Dialysis
Cancer – pulmonary
Cancer – gastrointestinal and liver
Non-cancer liver disease
Cancer – bladder and prostate
Cancer – gynaecological
Diabetes, insulin dependant
Diabetes, non-insulin dependant
Alcoholism
Over 65 years old
Less than 65 years, no other condition
(reference or general population)
Relative susceptibility
2584
1364
865
476
229
211
143
112
66
30
25
18
7.5
1
adapted from FAO (2004)
Risk based on meals served and prevalence rates
The potential risk can also be calculated using the information collected on the
number of meals served within establishments catering to the vulnerable population
and studies undertaken on the prevalence of pathogens in foods from these
establishments. As reported by Gillespie et al (2001) in the UK, 15/3494 (0.4%) of
cold sliced RTE meats where found to be of unacceptable / potentially hazardous,
due to the presence of high levels of E. coli, S. aureus, Listeria and C. perfringens 26.
Using the information collected by the NSW Food Authority on meals served and
assuming one meal per day consists of sliced cold meat and also assuming the
contamination rates in the UK and Australia are comparable, then it could be
expected that:
26
•
35,753 meals per annum served in childcare facilities that include sliced cold
meats could be potentially hazardous
•
142,432 meals per annum served in other establishments catering to the
vulnerable population could be potentially hazardous
Unacceptable / potentially hazardous was defined from categories in the Public Health Laboratory Service (PHLS)
Guidelines for the microbiological quality of some ready-to-eat foods at the point of sale (PHLS, 2000)
Page 113 of 189
Table 41 – Estimated cases of listeriosis for vulnerable population sub-groups for each food category, based on US data
Product
Dairy
Pasteurised fluid milk
High fat and other dairy products
Soft unripened cheese
Unpasteurised fluid milk
Fresh soft cheese
Ice-cream/frozen dairy products
Processed cheese
Hard cheese
Cultured milk products
Soft ripened cheese
Semi-soft cheese
Meat
Deli meats
Pâté and meat spreads
Frankfurters (reheated)
Dry/Semi-dry fermented sausages
Plant products
Fruit
Vegetables
Deli type salads
Seafood
Cooked RTE crustacean
Smoked seafood
Raw seafood
Preserved seafood
Intermediate age 27
Per serve 29
Per annum 30
Elderly 28
Per serve
Per annum
Perinatal
Per serve
Per annum
4.4 x 10-10
1.0 x 10-9
5.8 x 10-10
2.9 x 10-9
1.2 x 10-10
1.3 x 10-14
1.4 x 10-14
3.4 x 10-15
9.5 x 10-15
2.1 x 10-12
2.9x 10-12
2.6
1.4
0.2
0.09
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
3.4
8.3
4.9
2.2
1.0
9.2
9.3
9.2
5.6
2.2
3.0
x
x
x
x
x
x
x
x
x
x
x
10-9
10-9
10-9
10-8
10-9
10-14
10-14
10-15
10-14
10-11
10-11
4.2
2.9
0.4
0.1
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
1.5
3.2
2.0
9.9
4.2
6.5
6.7
8.1
4.7
1.3
1.6
x
x
x
x
x
x
x
x
x
x
x
10-7
10-7
10-7
10-7
10-8
10-12
10-12
10-13
10-12
10-9
10-9
0.7
0.3
0.04
0.03
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
<0.01
10-8
10-8
10-11
10-12
49.1
0.1
<0.01
<0.01
3.0
1.1
2.7
6.2
x
x
x
x
10-7
10-7
10-10
10-11
70.8
0.2
0.02
<0.01
1.2
4.5
1.6
3.7
x
x
x
x
10-5
10-6
10-8
10-9
13.4
0.03
<0.01
<0.01
5.0 x 10-12
8.4 x 10-13
1.7 x 10-13
0.02
<0.01
<0.01
5.1 x 10-11
8.2 x 10-12
1.4 x 10-12
0.05
<0.01
<0.01
2.8 x 10-9
4.8 x 10-10
8.8 x 10-11
<0.01
<0.01
<0.01
7.4 x 10-7
8.4 x 10-7
6.7 x 10-9
4.1x 10-9
0.03
<0.01
<0.01
<0.01
3.3
1.2
2.7
6.0
2.2
2.1
1.3
6.4
x
x
x
x
x 10-9
x 10-9
x 10-11
x 10-12
0.08
0.03
<0.01
<0.01
1.9
1.9
1.3
6.7
x 10-8
x 10-8
x 10-10
x 10-11
0.1
0.07
<0.01
<0.01
27
28
29
30
Intermediate age includes susceptible populations not captured in other groups (eg cancer, AIDS and transplant patients)
Elderly includes all elderly consumers in the population, not just those in aged care facilties
The risk per serving is inherent to the particular food category, and is therefore assumed to be the same in Australia as that calculated for the USA (FDA/USDA, 2003). This is based on the
assumption that consumption patterns for these foods are identical in Australia and the USA
The risk per annum has been adapted from USA population data contained in the FDA/USDA (2003) risk assessment of 260 million and extrapolated to Australian population data of
approximately 21.6 million (ABS, 2009) by dividing by a factor of 12
Page 114 of 189
As mentioned previously, the contamination rate of L. monocytogenes in RTE vegetables
and sandwiches from health care facilities in the Canada and UK were found to be 3.7%
and 2.5% respectively (Odumeru et al, 1997; Little et al, 2008). Again, assuming these
foods were served at one meal per day, the number of meals potentially contaminated
with L. monocytogenes would be:
•
330,724 meals per annum containing RTE vegetables at childcare facilities
•
1,137,498 meals per annum containing RTE vegetables at other facilities serving
to vulnerable populations
•
223,462 sandwiches served per annum at childcare facilities
•
890,201 sandwiches served per annum at other facilities catering to vulnerable
populations
These figures are likely to be an over estimation as exact information on meal types is
not known and it is likely that establishments will have risk managements strategies in
place to minimise the risks associated with food service to vulnerable populations. It is
also noted that the contamination rates for pathogens are extrapolated from data from
other countries.
Characterising the risk associated with other hazards within food service for vulnerable
populations is problematic due to the lack of information on the types of meals served
within these establishments. Other chapters within this document provide an estimation
of the risk for certain potentially hazardous foods and the risk posed is likely to be similar
for establishments serving food to the vulnerable population.
Control measures in food service for vulnerable populations
The risk characterisation and predicted number of listeriosis cases stated previously are
generally not observed due to the risk management strategies or control measures
implemented by establishments serving food to vulnerable populations. The main
strategy to assist in reducing the risk of foodborne illness at these establishments is the
effective development and implementation of a food safety program. Woody & Benjamin
(2008) provide an overview of the practicalities of implementing a food safety program in
healthcare settings. In addition, in implementing the requirements of Standard 3.3.1 –
Food Safety Program for Food Service to Vulnerable Populations of the Food Standards
Code, the NSW Food Authority developed guidance material to assist industry meet the
requirements (NSW Food Authority, 2008c). These documents provide some potential
control measures for establishments serving vulnerable populations including:
•
Substitution of high risk foods with lower risk alternatives
•
Effective cleaning and sanitation of fruits and vegetables to be consumed raw
•
Limited storage of pre-prepared infant formula
•
Minimise storage times of foods to be consumed without further heat treatment
•
Proper cooking of foods
•
Effective cleaning and sanitation of equipment, in particular those used for foods
that will not receive a further heat treatment
Page 115 of 189
Conclusion
A small sub-group within the population are known to be more susceptible to foodborne
illness. This group is generally referred to as the vulnerable population and includes
children under five years of age, the elderly over 65 and those with underlying immune
suppressant conditions. The hazards affecting the vulnerable population can be unique to
certain groups such as L. monocytogenes and C. sakazakii or may involve well known
foodborne pathogens such as Salmonella resulting in more severe illness in the
vulnerable persons.
This tends to be reflected in epidemiological data, where institutional outbreaks are overrepresented in the number of foodborne illness outbreaks, cases of illness and deaths
from food sources. Based on prevalence data for bacterial pathogens, it is estimated that
over one million of the 133 million meals served at institutions catering to vulnerable
populations in NSW each year may be potentially contaminated with a food pathogen.
This emphasises the importance in implementing control measures such as food safety
programs at establishments catering to the vulnerable populations, to ensure the safety
of their consumers.
Page 116 of 189
References – Food service to vulnerable populations
Acheson, D. & Lubin, L. (2008). Vulnerable populations and their susceptibility to foodborne
disease. In B. M. Lund & P. R. Hunter (Eds), The microbiological safety of food in healthcare
settings (pp. 290-319). Oxford: Blackwell Publishing Ltd.
Ashbolt, R. et. al (2002) Enhancing foodborne disease surveillance across Australia in 2001: the
OzFoodNet Working Group. Communicable Diseases Intelligence, 26(3), 375-406.
ABS [Australian Bureau of Statistics] (2005). 4402.0 Child care survey. Retrieved 30
November2008, from
http://www.ausstats.abs.gov.au/ausstats/subscriber.nsf/0/4FB69C9AE4BBC0EBCA257186007BAA
38/$File/44020_nsw.xls.
ABS [Australian Bureau of Statistics] (2008). 3101.0. Australian demographic statistics. Retrieved
22 October 2008, from
http://www.ausstats.abs.gov.au/ausstats/subscriber.nsf/0/B6C3FC4377C676B9CA2574CD001250C
1/$File/31010_mar%202008.pdf.
Bates, J.R. & Bodnaruk, P.W. (2003). Clostridium perfringens. In Hocking, A.D. (Ed.) Foodborne
Microorganisms of Public Health Significance (pp 479-504). Australian Institute of Food Science
and Technology, Waterloo.
Buzby, J. C. (2002). Older adults at risk of complications from microbial foodborne illness. Food
Review, 25(2), 30-35.
Cox, B. & Bauler, M. (2008). Cook chill for food service and manufacturing: guidelines for safe
production, storage and distribution. Alexandria: Australian Institute of Food Science and
Technology.
Desmarchelier, P.M. (2003). Pathogenic vibrios. In Hocking, A.D. (Ed.) Foodborne Microorganisms
of Public Health Significance (pp. 333-358). Australian Institute of Food Science and Technology,
Waterloo.
Desmarchelier, P.M. & Fegan, N. (2003) Enteropathogenic Escherichia coli. In Hocking, A.D. (Ed.)
Dierick, K., Van Coillie, E., Swiecicka, I., Meyfroidt, G., Devlieger, H., Meulemans, A.,
Hoedemaekers, G., Fourie, L., Heyndrickx, M., & Mahillon, J. (2005). Fatal Family Outbreak of
Bacillus cereus-associated Food Poisoning. Journal of Clinical Microbiology, 43(8), 4277-4279.
FAO [Food and Agricultural Organization of the United Nations] (2004). Risk assessment of
Listeria monocytogenes in ready-to-eat foods. Retrieved 17 October 2008, from
ftp://ftp.fao.org/es/esn/jemra/mra4_en.pdf
FAO [Food and Agricultural Organization of the United Nations] (2007). Enterobacter sakazakii
and Salmonella in powdered infant formula: meeting report, MRA series 10. Retrieved 19
November 2008, from http://www.who.int/foodsafety/publications/micro/es.pdf.
FAO [Food and Agricultural Organization of the United Nations] (2008). Microbiological risk
assessment series: Enterobacter sakazakii (Cronobacter spp.) in powdered follow-up formulae.
Retrieved 17 October 2008, from
http://www.fao.org/ag/agn/agns/jemra/Sakazaki_FUF_report.pdf.
Quantitative assessment of relative risk to public health from foodborne Listeria monocytogenes
among selected categories of ready-to-eat foods. Retrieved 30 October 2008, from
http://www.foodsafety.gov/~dms/lmr2-toc.html.
Food Science Australia & Minter Ellison Consulting (2002). National Risk Validation Project. Final
Report.
FSANZ [Food Standards Australia New Zealand] (2006). Final assessment report. Proposal P288.
Food safety program for food service to vulnerable populations. Canberra, ACT: Author.
Page 117 of 189
FSANZ [Food Standards Australia New Zealand] (2008). Australia New Zealand Food Standards
Code. Standard 3.3.1 – Food safety programs for food service to vulnerable populations.
Retrieved October 30, 2008, from
http://www.foodstandards.gov.au/_srcfiles/Standard_3_3_1_FSPs_%20Vulnerable_pops_v95.pdf.
Gillespie, I., Little, C. & Mitchell, R. (2001). Microbiological examination of cold ready-to-eat sliced
meats from catering establishments in the United Kingdom. Journal of Applied Microbiology,
88(3), 467-474.
Goulet, V., Hedberg, C., Le Monnnier, A. & de Valk, H. (2008). Increasing incidence of listeriosis in
France and other European countries. Emerging Infectious Disease, 14(5), 734-740.
ILSI Research Foundation/Risk Science Institute (2005). Achieving continuous improvement in
reductions in foodborne listeriosis – a risk-based approach. Journal of Food Protection. 68(9),
1932-1994.
Microorganisms in Foods 5: Microbiological specifications of food pathogens. Roberts, T.A., BairdParker, A.C. & Tompkin, R.B. (Eds.). Blackie Academic & Professional, London.
Jay, S., Davos, D., Dundas, M., Frankish, E. & Lightfoot, D. (2003). Salmonella. In Hocking, A.D.
(Ed.) Foodborne Microorganisms of Public Health Significance (pp. 207-266). Australian Institute
of Food Science and Technology, Waterloo.
Lehner, A. & Stephan, R. (2004). Microbiological, epidemiological and food safety aspects of
Enterobacter sakazakii. Journal of Food Protection, 67(12), 2850-2857.
Little, C.L., Barrett, N.J., Grant, K. & McLauchlin, J. (2008). Microbiological safety of sandwiches
from hospitals and other health care establishments in the United Kingdom with a focus on
Listeria monocytogenes and other Listeria species. Journal of Food Protection, 71(2), 309-318.
MLA [Meat & Livestock Australia] (2003). Through chain risk profile for the Australian red meat
industry, PRMS.038c, part 1: risk profile. North Sydney: Meat & Livestock Australia.
NSW Food Authority (2008a). Regulatory impact statement: food amendment (child care centres)
regulation 2008. Sydney: NSW Food Authority.
NSW Food Authority (2008b). Regulatory impact statement: food amendment (vulnerable persons
food safety scheme) regulation 2008. Sydney: NSW Food Authority.
NSW Food Authority (2008c). Vulnerable persons food safety scheme manual: policy and
information to help businesses comply with the food service to vulnerable populations food safety
scheme under the Food Regulation 2004. Retrieved 11 December 2008, from
http://www.foodauthority.nsw.gov.au/_Documents/industry_vp_pdf/vulnerable_persons_food_saf
ety_scheme_manual_compl.pdf.
NSW Health (2008). Salmonellosis notification in NSW residents. Retrieved 15 October 2008, from
http://www.health.nsw.gov/data/diseases/salmonellosis.html.
O’ Brien, S.J. (2008). Foodborne Disease Outbreaks in Healthcare Setting. In Lund, B.M. &
Hunter, P.R. (Eds.), The microbiological safety of food in healthcare settings (pp. 251-289).
Oxford: Blackwell Publishing Ltd.
Odumeru, J.A, Mitchell, S.J., Alves, D.M., Lynch, J.A., Yee, A.J., Wang, S.L., Styliadis, S. and
Farber, J.M. (1997). Assessment of the microbiological quality of ready-to-use vegetables from
health-care food services. Journal of Food Protection, 60(8), 954-960.
OzFoodNet Working Group (2003). Foodborne disease in Australia incidence, notifications and
outbreaks. Annual report of the OzFoodNet network, 2002. Communicable Diseases Intelligence,
27(20), 209-243
OzFoodNet Working Group (2004). Foodborne disease investigation across Australia: Annual
report of the OzFoodNet network, 2003. Communicable Diseases Intelligence, 28(3), 359-389.
OzFoodNet Working Group (2005). Reported foodborne illness and gastroenteritis in Australia:
Annual report of the OzFoodNet network, 2004. Communicable Diseases Intelligence, 29(2), 164190.
Page 118 of 189
OzFoodNet Working Group (2006). Burden and causes of foodborne disease in Australia: annual
report of the OzFoodNet network, 2005. Communicable Diseases Intelligence, 30(3), 278-300.
OzFoodNet Working Group (2007). Monitoring the incidence and causes of disease potentially
transmitted by food in Australia: Annual report of the OzFoodNet, 2006. Communicable Disease
Intelligence, 31(4), 345-365.
PHLS [Public Health Laboratory Service, UK). (2000). Guidelines for the microbiological quality of
some ready-to-eat foods samples at the point of sale. Communicable Disease and Public Health
3(3), 163-167.
Stewart, C. (2003). Staphylococcus aureus and staphylococcal enterotoxins. In Hocking, A.D.
(Ed.) Foodborne Microorganisms of Public Health Significance (pp. 359-379). Australian Institute
of Food Science and Technology, Waterloo.
Sutherland, P., Miles, D. & Laboyrie, D. (2003). Listeria monocytogenes. In Hocking, A.D. (Ed.)
Szabo, E. A. & Gibson, A. M. (2003). Clostridium botulinum. In Hocking, A.D. (Ed.) Foodborne
Microorganisms of Public Health Significance (pp. 505-542). Australian Institute of Food Science
and Technology, Waterloo.
Tallis, G., et al. (1999). A nursing home outbreak of Clostridium perfringens associated with
pureed food. Australian and New Zealand Journal of Public Health. 23(40), 421-423.
Wall, P. (2008). Overview. In Lund, B.M. & Hunter, P.R. (Eds.), The microbiological safety of food
in healthcare settings (pp. 1-11). Oxford: Blackwell Publishing Ltd.
Woody, J-M. & Benjamin, D.L. (2008). Practical implementation of food safety management
systems in healthcare setting. In Lund, B.M. & Hunter, P.R (Eds.), The microbiological safety of
food in healthcare settings (pp. 351-380). Oxford: Blackwell Publishing Ltd.
Page 119 of 189
Egg food safety scheme
The NSW Food Authority previously undertook a risk profile on the NSW egg industry
(Miles & Chan, unpublished) and proposed several risk management strategies to
underpin the incorporation of an Egg food safety scheme into the Food Regulation 2004.
As SafeFood NSW, the Authority commissioned Food Science Australia to provide a
scoping study on plant products, which also examined eggs (FSA, 2000). This report
identified potential hazards associated with the production of eggs and egg products,
shown in Table 42.
In addition the egg industry’s peak body, the Australian Egg Corporation Ltd (AECL)
commissioned the South Australian Research and Development Institute (SARDI) to
complete two sections of work, a risk profile on eggs and egg products to examine all
potential hazards (Daughtry et al, 2005), and a quantitative risk assessment
concentrating on evaluating the risks from Salmonella serovars (Thomas et al, 2006)
All bodies of work include comprehensive assessments of both microbiological and
chemical hazards in eggs and egg products.
Risk assessment work on the Australian egg industry is currently being undertaken by
FSANZ to underpin the development of the Primary Production and Processing Standard
for Eggs, Proposal P301 (FSANZ, 2006).
Microbiological hazards
In an assessment of microbiological standards for eggs and egg products, the former
Australia New Zealand Food Authority (now FSANZ) identified the following
microorganisms of concern in relation to the commercial production, processing and
distribution of eggs (ANZFA, 1999):
•
Salmonella serovars
•
Bacillus cereus
•
•
It is recognised that pathogenic organisms may contaminate the shell of the egg,
through environmental and faecal contamination. B. cereus (van Netten et al, 1990),
L. monocytogenes (McKellar, 1993) and S. aureus (Papadopoulou et al, 1997) have all
been detected during analysis of eggs and/or egg products. However, an analysis of
foodborne illness attributed to eggs in Australia shows that virtually all outbreaks have
been due to Salmonella serovars, with S. Typhimurium the dominant serovar responsible
for illness associated with egg consumption.
A risk profile undertaken by the NZFSA concentrated on non typhoidal Salmonella in and
on eggs as the main hazard (Lake et al, 2004) and the AECL quantitative risk assessment
work focused on Salmonella as the primary hazard of concern.
Page 120 of 189
Table 42 – Hazards in the production of shell eggs and egg products
Product
Shell eggs
Egg products
Hazard / contributing factors
Contamination with Salmonella serovars
Growth of Salmonella serovars
Contamination with other pathogens
Penetration of pathogens during egg production and handling
Pathogen survival due to undercooking
Development of antibiotic resistant pathogens
Mycotoxins
Pyrrolizidine alkaloids from feed transferred to eggs
Heavy Metals
Agricultural and veterinary chemicals
Pesticide residues (eg organochlorine residues) in free range and
‘backyard’ eggs
Polychlorinated biphenyls
Potential contamination of eggs or egg products from packaging
Contamination with Salmonella serovars or other pathogens
Pathogen survival due to inadequate process treatment
Contamination of raw and processed product with heavy metals,
chemicals (including agricultural compounds and veterinary medicines) or
other toxicants
adapted from FSA (2000)
Overseas, the focus of egg safety assessment has been slightly different, as Salmonella
Enteritidis has become endemic in overseas laying flocks since the 1980s. This has
provided a major problem for the overseas egg industry as Salmonella Enteritidis has the
unusual ability to colonise the ovarian tissue of hens and this causes Salmonella cells to
be present within the contents of newly laid intact shell eggs. Contamination of eggs and
of egg products with Salmonella Enteritidis is believed to be the cause of the large
increase in human infections in Europe and North America. The Centre for Disease
Control in the USA attributed 77-82% of Salmonella Enteritidis-related foodborne
outbreaks to eggs and egg products. In many of these cases the outbreaks were
associated with the consumption of ‘Grade A’ shell eggs (WHO, 2002).
Currently Australian layer flocks remains free of Salmonella Enteritidis, and it has been
estimated that this is worth around $48 million per annum to the Australian egg industry
(Sergeant et al, 2003). Given this, there is a strong push from the industry peak body,
the AECL, for the implementation of quality assurance programs and codes of practice in
the industry, including biosecurity measures on farm to ensure the maintenance of the
Salmonella Enteritidis-free status (AECL, 2005a, AECL, 2005b). However, other
Salmonella serotypes are intrinsic in the Australia poultry industry and form part of the
microbiota in the intestinal tract of chickens.
The external surfaces of eggs may become contaminated with faecal material, including
Salmonella bacteria between when the egg is laid and when it is collected. However, if
the egg is kept dry it is likely that the bacteria will die on the outside of the shell. In a
survey of Australian farms that included testing of faecal samples and egg pulp, Cox et al
(2002) found that S. Singapore was the dominant organism. This was thought to be
related to the high numbers of Salmonella found in the feed intended for the chickens,
which in turn showed in the numbers found in the faecal specimens. Survival of
Salmonella on the egg surface may be enhanced by high relative humidity and the
organism may penetrate the egg shell if it is wet, as the shell becomes more porous. Cox
et al (2002) showed that S. Infantis, S. Typhimurium, S. Heidelberg and S. Singapore
were all capable of migrating into the egg under favourable conditions.
Page 121 of 189
Normally the contents of an intact shell egg are essentially sterile when laid and the
intrinsic structure of an egg, with the cuticle, shell and shell membranes combining to
form a protective barrier against bacteria penetrating into the egg. However, if the egg is
cracked (the shell is cracked but the shell membrane is intact) or broken (shell is cracked
and shell membrane is also broken), this can facilitate access of pathogenic bacteria into
the egg contents, where they may be able to increase in numbers in the nutrient-rich
yolk.
Standard 2.2.2 – Egg and Egg Products of the Food Standards Code prohibits cracked
eggs being made available for retail sale or for catering purposes, due to the increased
risk of bacterial contamination. However, there is anecdotal evidence to suggest that
cracked eggs are being sold at a substantially reduced price for use in restaurants and
for catering purposes. A Canadian risk assessment on the use of cracked eggs stated
that any country producing eggs has to recognise that, despite regulations controlling
the use of cracked eggs, economics will dictate that some of these will be consumed as
whole eggs and a management plan is desirable to limit hazardous practices associated
with these eggs (Todd, 1996).
Chemical hazards
Dawson et al (2001) listed the possible sources of chemical contamination of eggs
including:
•
free range birds feeding on contaminated soil
•
insecticide sprays used while birds are present
•
water medication at incorrect rate
•
eggs washed in inappropriate solutions
•
egg washing compound mixed at wrong concentrations
•
systemic pesticides used in grower sheds
•
shed fumigation while birds are present
•
chemical feed additives included at wrong rate
•
use of antibiotics or other veterinary medicines
Survey results from the National Residue Survey (NRS) and Market Basket Survey have
shown occasional detections of heavy metals. Dieldrin residues have also been found in
free range eggs (FSA, 2000). Free range hens are considered a higher risk for coming
into contact with environmental chemical contaminants because they have the
opportunity to source their own food outside, thus increasing the potential for eating
contaminated vegetation or soil. However, all detections have been at levels well below
the Maximum Residue Level (MRL), and the health risk to humans was concluded to be
low.
There have been detections of veterinary chemical residues in eggs above the MRL, in
the past several years (Table 43). The use of antiprotozoals is common to control
coccidiosis in the hens, and is mainly used as a feed additive. The traceback
investigations of positive detections on farm have tended to indicate mix ups with feed.
The use of cages has reduced the need for veterinary chemical usage because the hens
are housed off the floor and parasitic infections are less of a problem (FSA, 2000).
The AECL risk profile concluded that there was no evidence that pesticides, veterinary
medicines or other chemical contaminants, present a food safety or public health risk
(Daughtry et al, 2005). Despite occasional low level detections, in general eggs are
residue free and no egg samples have been found to contain chemical residues which
would present an immediate health risk.
Page 122 of 189
Table 43 – Prevalence of chemical residues in eggs
National
Number of
Number with
Number of residues above MRL
Residue
analyses
residues
Survey
1991
617
21 (3.4%)
1 (0.16%)
1992
564
30 (5.3%)
2 (0.35%)
1997
228
1 (0.44%)
0
National
Number of
Number of
Residues above
Residues
Residue
samples
analyses
MRL/ERL
above ML
Survey
1998
248
703
0
0 31
1999
83
1190
0
0 32
1999–2000
158
3242
0
1 33
2000–2001
122
1683
0
0
2001–2002
92
1387
0
0
No testing of eggs was conducted in 2002–2003 or 2003–2004
2004–2005
75
1000
2 34
0
2005–2006
75
1000
2 35
0
2006–2007
75
1025
2 36
0
adapted from BRS (1996); BRS (1998); AFFA (1999); AFFA (2000); AFFA, (2001); AFFA (2002); DAFF
(2003); DAFF (2005); DAFF (2006); DAFF (2008)
Physical hazards
Due to the protection offered by the shell of the egg, there is a very small likelihood of
physical contaminants affecting eggs. The main physical hazards present on farm are
blood spots, rodent droppings and insects. Blood spots may be present in eggs when
they are laid and may reach the consumer if the eggs are not carefully checked during
grading. The candling process used for crack detection of commercial eggs should
prevent eggs containing physical contaminants from entering the market. FSANZ
concluded that physical hazards are not a significant issue for eggs and egg products
(FSANZ, 2006).
Other eggs
The Australian egg industry is primarily based on eggs and egg products produced from
hens. Other egg-producing avian species, such as ducks, quails, pheasants, pigeon,
geese, turkey and guinea fowl form a very minor part of the egg market. There is little
detailed information available about the national production of eggs and egg products
from these species (FSANZ, 2006), or on the microbiological and chemical status of these
products. There is some evidence to suggest that duck eggs may be more highly
contaminated with Salmonella serovars than chicken eggs. Overseas studies have shown
up to 14% of duck eggs contaminated with Salmonella serovars This is possibly due to
the added potential for external contamination of the eggs from less on-farm controls,
but also through an increased probability of vertical transmission, particularly of
Salmonella with ducks (Jay et al, 2003).
31
32
33
34
1998 – two Dieldrin residues detected in free-range eggs, at concentrations of less than 20% MRL
1999 – one residue of Dieldrin in free-range eggs, at concentrations of less than 20% MRL
1999–2000 – one residue of copper above the ML was detected
2004 –2005 – both residues were due to anticoccidials. One sample containing Lasalocid was thought to be the result
of a mix-up with feed. The traceback for sample containing Nicarbazin was not complete when the NRS report was
published.
35
2005–2006–two samples showed residue levels of Nicarbazin (anticoccidial) above the Australian Standard and were
found to be the result of a mix-up with feed.
36
2006–2007 – two samples showed residue levels of Nicarbazin (anticoccidial) above the Australian Standard and were
found to be the result of a mix-up with feed.
Page 123 of 189
Most duck eggs are processed into specialty products, such as salted eggs, century eggs
and Balut egg. While the primary microbiological hazard of concern remains Salmonella
serovars, the manual handling associated with specialty egg production could possibly
lead to contamination with other pathogens such as S. aureus and E. coli.
The NSW Food Authority has detected high level of lead in century eggs made from duck
eggs (McCreadie et al, 2007). Traditional practices involved the use of lead oxide in the
pickling solution, believed to modify the porosity of the egg shell, and thus influence the
rate of ingress of the alkaline pickling solution into the egg. This was thought essential to
produce century eggs with the desirable semi-solid yolk texture. The Authority survey
found a single NSW processor adding lead oxide to the brine the eggs were soaked in.
Lead oxide can be extremely poisonous and is not permitted as a food additive in
Australia. Given the traditional use of lead salts in specialty egg products, there may be a
need to monitor the lead content of these products periodically in case of processors go
back to a ‘proven’ traditional technique.
Exposure assessment
Consumption of shell eggs (‘table eggs’)
In NSW, it is estimated there are 139 egg producers with annual production of almost 58
million dozen eggs worth an estimated $90 million per annum (ABS, 2006). While egg
consumption has been steadily declining, consumption data from 1998–99 indicates that
the Australian population consumes an average 137 eggs per person each year (ABS,
2000). The National Nutrition Survey (ABS, 1995) reported that 16.1% of the NSW
population consumed eggs and egg products (see Table 45). Overall results showed that
rates of consumption ranged from 8.5% (females aged 16 to 18) to 20.5% (males aged
45 to 64). Of those males consuming eggs and egg products, average daily consumption
varied from 27.8 g/day (2 to 3 years) to 74.0 g/day (12 to 24 years), while for females
average daily consumption varied from 43.0 g/day (2 to 3 years) to 50.0 g/day (25 to 44
years).
The consumption data only recorded the consumption levels of eggs (eg fried egg,
poached egg) and dishes where egg was the major ingredient (eg omelette, soufflé,
scrambled eggs). It did not record consumption of foods where egg may be included as
one of many ingredients (eg mayonnaise, desserts).
The national consumption data reveals that between 12–13% of infants (2–3 yrs) and
14–17% of the elderly (65+ yrs) regularly consume eggs. No distinction was made in
what form the eggs were consumed, whether they were served lightly or thoroughly
cooked. This demonstrates that a significant proportion of the vulnerable population are
regular consumers of eggs.
Page 124 of 189
Prevalence of Salm onella in Australian eggs
Survey data included in the AECL risk assessment provides the best prevalence data of
Salmonella serovars on and within Australian eggs (Thomas et al, 2006). The external
surface of 11,036 eggs from various sources (caged, free range and barn-laid) and the
internal contents of 20,000 caged egg samples were sampled (see Table 44).
Table 44 – Prevalence of Salm onella in Australian eggs
Egg type
Shell eggs – ungraded
Caged (shell)
Free range (shell)
Barn laid (shell)
Shell eggs – graded
Caged (shell)
Caged (internal contents)
Number of samples
tested
Salm onella detected
(estimated prevalence)
2160
1200
1200
0 (0 – 0.2%)
0 (0 – 0.3%)
0 (0 – 0.3%)
6476
20,000
0 (0 – 0.06%)
0 (0 – 0.02%)
adapted from Daughtry et al (2004)
Based on comparable prevalence of external contamination to overseas data (0.21%),
Thomas et al. (2006) concluded that the prevalence of internal contamination by
Salmonella in Australian eggs is likely to be close to the overseas reported rate of
0.004%, roughly equivalent to one egg every 25,000 being contaminated with
Salmonella. This prevalence must be considered in the context that there are over 800
million eggs consumed in NSW each year, both as shell eggs and as an ingredient in
food. At this prevalence, there may be 32,000 eggs contaminated with Salmonella
consumed each year in NSW.
Table 45 – Consumption of eggs and egg products in Australia
Sex
Age
Male
Male
Male
Male
Male
Male
Male
Male
Male
Female
Female
Female
Female
Female
Female
Female
Female
Female
2–3
4–7
8 – 11
12 – 15
16 – 18
19 – 24
25 – 44
45 – 64
65+
2–3
4–7
8 – 11
12 – 15
16 – 18
19 – 24
25 – 44
45 – 64
65+
consuming egg products and
dishes 37
(%)
12.6
11.1
14.0
12.3
18.1
15.7
17.9
20.5
17.6
13.9
12.2
10.7
8.7
8.5
12.8
15.2
16.8
14.2
consumers of egg products and
dishes
(g/day)
27.8
50.0
58.0
74.0
74.0
74.0
62.5
57.0
72.0
43.0
50.0
50.0
50.0
49.0
50.0
50.0
50.0
50.0
37
Egg products and dishes are defined in the National Nutrition Survey (ABS, 1995) as including the following:
- Eggs
- Dishes where egg is the major ingredient
- Egg substitutes and dishes
Page 125 of 189
Use of shell eggs
It is estimated that 87% of all egg production is sold at retail as shell eggs, with the
remaining 13% being further processed into egg products such as pasteurised liquid egg
(ABS, 2000). Where egg products are processed, they must meet prescribed
microbiological criteria under Standard 1.6.1 – Microbiological Limits for Food of the Food
Standards Code. Of those eggs sold at retail, it is estimated that 30% are used as an
ingredient in a food where it will be thoroughly cooked.
There is little data on the consumption patterns of eggs by Australian consumers, but an
American survey estimated that 27% of all egg dishes consumed in the US are lightly
cooked (Lin et al, 1997), translating to each person on average consuming lightly cooked
eggs 20 times a year. Lightly cooked eggs are described as ‘runny’, ‘runny yolk’ or ‘runny
white’ and may allow the survival of any pathogenic bacteria that are present within the
egg. Eggs fried ‘over easy’ and ‘sunny side up’ accounted for almost half (49%) of the
lightly cooked eggs eaten. Of instances where raw eggs were consumed as an ingredient
in an uncooked or very lightly cooked food, 52% was in frosting, salad dressing (18.5%),
blended milk beverages (16%), homemade ice-cream (6%), and hollandaise sauce.
Although Australian consumption patterns may be different to the American data cited
here, this does provide an indication of the potential exposure to pathogens from
undercooked eggs.
Consumption of specialty duck egg products and quail eggs
Production data on specialty egg products is limited, and it is assumed that the level of
consumption forms a very small portion of overall egg consumption. Moreover, they are
likely to be consumed by specific minority groups and/or as delicacies only occasionally
rather than as part of routine diet. A per capita consumption figure is not available for
these products.
Foodborne illness outbreaks from eggs
A summary of foodborne illness outbreaks attributed to eggs, or where egg was used as
an ingredient in the implicated food is shown in Table 46 (more detailed information on
these outbreaks is included in Table 70 of Appendix 3). It is clear from epidemiological
data and the literature that Salmonella serovars is the primary pathogen of concern in
relation to foodborne illness associated with eggs.
Table 46 – Summary of foodborne illness outbreaks attributed to eggs, egg products
and eggs used as an ingredient
Hazard
Salmonella serovars
Streptococcus pyogenes
Toxin
Norovirus
Campylobacter
Unknown
Total
Australian
outbreaks
(1995–2008)
103
1
1
1
1
3
110
Cases
Hospitalisations
3808
72
16
11
2
32
3941
265
0
0
0
1
0
266
Deaths
0
0
0
0
0
0
0
Page 126 of 189
Effect of yolk mean time (YMT) on exposure to Salm onella
While it appears inevitable that Salmonella will penetrate into a small proportion of eggs,
the bacteria will not begin to increase in numbers immediately. Studies have shown that
Salmonella will not grow in the iron restricted environment of the albumen (egg white),
and is only able to grow after a considerable period of time. As the egg ages, the
vitelline membrane surrounding the yolk breaks and allows the Salmonella to enter the
yolk and utilise the rich iron supply within the yolk to grow and rapidly increase in
numbers. This length of time for the membrane to break down is determined by the yolk
mean time (YMT) and is affected by the temperature the egg is stored at. Humphrey
(1994) observed large numbers of Salmonella in both the yolk and albumen after the
resolution of YMT.
Thomas et al. (2006) estimated that 75% of eggs in Australia are consumed before
resolution of YMT, based on average industry practices and storage temperatures
throughout the production, distribution and retail chain. In effect, this minimises the
opportunity for Salmonella to proliferate to high numbers within the egg and results in
eggs being a low risk food. However, where eggs are stored at elevated temperatures
for extended periods of time, this can allow the YMT to resolve and provide the
conditions for any Salmonella which may be present in the egg to grow. Under these
conditions, the risk of foodborne illness is increased unless the egg is fully cooked prior
to consumption to eliminate the Salmonella.
Grading and processing of eggs
Several processes used in the grading and processing of eggs may lead to cross
contamination of eggs and egg products if sufficient food safety controls are not in place.
Efficient crack detection is required when the eggs are graded to ensure that cracked
eggs are identified and are re-directed for further processing where they will be
pasteurised or an equivalent treatment. To ensure the efficacy of the crack detection
method, it should be validated and verified.
Washing of eggs is sometimes undertaken by graders and processors to remove any
gross faecal or environmental contamination from the shell of the eggs prior to sale.
However, if not carefully controlled, the washing process has the potential to damage
the shell cuticle and actually increase the risk of microbial penetration into the egg.
Inadequate control of temperature, pH and insufficient changes in wash water can result
in a build up of microorganisms and lead to cross contamination of eggs. In addition, the
incorrect use of chemicals has the potential to cause unacceptable levels of chemical
residues in the egg. Eggs must be dried after washing as inadequately dried eggs can
allow microbial growth and any remaining bacteria may be aspirated into the egg.
The design and hygiene of equipment used in the processing of eggs is of considerable
importance to avoid niches for bacterial growth (Jones et al, 2003). The method used to
separate the egg contents from the shell for further processing into liquid pulp can have
a major impact on the microbiological content of the resulting pulp. The risk of bacterial
contamination is markedly worsened by the use of dirty eggs. Liquid egg pulp made from
cracked or broken eggs is more likely to be associated with pathogens or increased
pathogen numbers than pulp prepared from intact shell eggs.
Industry practice is to discard broken eggs, as they are considered a microbiological risk
for both safety and quality. The exception to this appears to be where eggs may be
broken just prior to when they are pulped. The production of egg products must involve
pasteurisation, with the minimum times and temperatures defined in Standard 1.6.2 –
Processing Requirements of the Food Standards Code, or an equivalent treatment may
be used. Pasteurisation of egg pulp must deliver a sufficient heat treatment to ensure
the finished product complies with the microbiological standards specified in Standard
Page 127 of 189
1.6.1 – Microbiological Limits for Food of the Food Standards Code. The pasteurisation
process for egg pulp is relatively mild as coagulation of the egg protein needs to be
avoided (ICMSF, 1998). The effectiveness of the pasteurisation process is influenced by
the microbial load, so the higher the bacterial load prior to pasteurisation, the higher the
bacterial population remaining after processing. Thomas et al. (2006) demonstrated that
the pasteurisation parameters set by the Food Standards Code delivers a relatively small
log reduction of Salmonella for liquid egg yolk and albumen and the presence of viable
Salmonella in processed products has been demonstrated (NEPSS, 2003). To ensure the
effectiveness of the pasteurisation process, the process must be monitored and verified
through end product testing and additional control measures implemented to limit the
extent of contamination, and the opportunity for growth of contaminating organisms in
the raw material.
Hygienic handling of pasteurised product must be undertaken to ensure pasteurised
product is not recontaminated. Egg pulp remains vulnerable to further contamination
post pasteurisation if GMP and GHP are not implemented. Salmonella serovars are able
to grow rapidly in egg yolk under both aerobic and anaerobic conditions (ICMSF, 1998),
unless the product is stored under appropriate temperature control or kept in a frozen
state.
Specialty duck egg products
Production of processed duck eggs exposes the eggs to greater risks of invasion by
pathogens likely to be found in the prevailing environment (eg Salmonella serovars). The
extensive manual handling these products receive may also introduce pathogens such as
S. aureus and E. coli. However, reported cases of illness implicating these pathogens in
processed duck eggs are rare.
Salted duck eggs and Balut eggs are intended to be eaten cooked. The one documented
case of Salmonella poisoning implicating salted eggs was probably an example of
uninformed use of that product (Campbell, pers comm.). There is a high risk of chemical
contamination with the use of non-food grade chemicals such as lead oxide, if processors
resort to traditional methods for making century eggs.
The primary hazard to human health from eggs and egg products are Salmonella
serovars. This is evident from the epidemiological data, with Salmonella serovars
determined as the cause for the majority of foodborne illness cases attributed to eggs in
Australia. While it is possible that other pathogens may also contaminate the shell of the
egg through faecal and environmental contamination, this is not reflected in foodborne
illness data across Australia.
In the AECL-funded risk profile, Daughtry et al (2005) examined 33 different scenarios of
egg production and storage and final usage. An estimate was made of how many eggs
were captured by each scenario, and an estimate made of the risk per serving and
predicted annual number of illnesses attributable to each (see Table 47). It is
acknowledged that there are a number of assumptions made in generating such
predictions, however this information can provide a useful indication of the highest risk
practices and be used to focus risk management strategies.
Page 128 of 189
Table 47 – Risk ranking for type and use of eggs
growth
(YMT
resolved)
Eggs subjected to pathogen reduction step (eg cooking)
1. Commercial eggs
Intact
None
Salm onella
Risk
ranking
Predicted cases of
Salmonellosis per
serve
(in Australia)
Predicted annual number of
Salmonellosis cases (in
Australia) 42
MR
Low
4 x 10-11
3.34 x 10-2
2.
Commercial eggs
Intact
None
SR
Low
4 x 10-14
3.34 x 10-5
3.
Commercial eggs
Intact
None
RE
Low
0
0
Scenario
Cracked/Intact
Salm onella
kill step
MR 38, SR 39,
RE 40, NE 41
-6
4.
5.
Commercial eggs
Commercial eggs
Intact
Intact
5-log
5-log
MR
SR
Medium
Low
4 x 10
4 x 10-9
772
7.72 x 10-1
6.
Commercial eggs
Intact
5-log
RE
Low
0
0
-11
7.
Non-commercial eggs
Intact
None
MR
Low
4 x 10
3.43 x 10-3
8.
9.
Non-commercial eggs
Non-commercial eggs
Intact
Intact
None
None
SR
RE
Low
Low
4 x 10-14
0
3.43 x 10-6
0
10. Non-commercial eggs
Intact
5-log
MR
Medium
4 x 10-6
79
-9
Intact
5-log
SR
Low
4 x 10
7.92 x 10-2
Intact
Cracked
5-log
None
RE
MR
Low
Low
0
4 x 10-9
0
1.32 x 10-3
Cracked
None
SR
Low
4 x 10-12
1.32 x 10-6
Cracked
None
RE
Low
0
0
-4
Cracked
Cracked
5-log
5-log
MR
SR
Medium
Low
4 x 10
4 x 10-7
66
6.60 x 10-2
Cracked
5-log
RE
Low
0
0
38
39
40
41
42
MR – moderate reduction – 100-fold decimal reduction in Salmonella (eg light cooking, fried ‘sunny side up’, microwave, boiled where liquid yolk remains)
SR – substantial reduction – 10,000 fold decimal reduction in Salmonella (eg fried ‘easy over’, lightly scrambled or omelette, pasta)
RE – reliably eliminates – 1,000,000,000 fold decimal reduction in Salmonella (eg hard boiled or scrambled, cakes, biscuits)
NE - no effect – no reduction in Salmonella (eg raw egg drinks, some desserts)
Data from Daughtry et al (2005) used an Australian population figure of 19.5 million. These estimates have been extrapolated to the current population of Australia estimated by ABS (2009) as
approximately 21.6 million, by multiplying by a factor of 1.1, for consistency with other sections of this risk assessment.
Page 129 of 189
Consumed without pathogen reduction step in raw egg drinks and cold desserts
19. Commercial eggs
Intact
None
NE
Low
4.0 x 10-9
2.57 x 10-1
20. Commercial eggs
Intact
5-log
NE
Medium
4 x 10-5
643
Intact
Intact
None
5-log
NE
NE
Low
Medium
4.0 x 10
4 x 10-5
7.92 x 10-2
198
Cracked
None
NE
Low
4 x 10-7
1.32 x 10-2
Cracked
5-log
NE
Medium
4 x 10-4
13
-6
10
Cracked eggs in
egg butter
-9
3-log
NE
High
4 x 10
1-log
NE
Medium
2.5 x 10-4
-6
Commercial liquid egg pulp
26. Commercial eggs
Unpasteurised pulp
11
27. Commercial eggs
28. Commercial eggs
Unpasteurised pulp
Unpasteurised pulp
1-log
1-log
SR
RE
Medium
Low
2.5 x 10
2.50 x 10-9
2.15 x 10-1
2.68 x 10-4
29. Commercial eggs
Unpasteurised pulp
1-log
MR
Low
0
0
30. Commercial eggs
Pasteurised pulp
None
NE
Low
2 x 10-7
10
-9
31. Commercial eggs
32. Commercial eggs
Pasteurised pulp
Pasteurised pulp
None
None
SR
RE
Low
Low
2.00 x 10
2.00 x 10-12
1.29 x 10-1
1.29 x 10-4
33. Commercial eggs
Pasteurised pulp
None
MR
Low
0
0
adapted from Daughtry et al (2005)
Page 130 of 189
The highest risk per serving was for scenarios where the storage conditions of the
eggs allowed the YMT to be resolved and therefore allowed the numbers of
Salmonella to significantly increase (scenario 16, 24 from Table 47), resulting in a
risk per serving of 400 predicted illnesses per million servings. However, this did not
necessarily translate to a large number of predicted illnesses, as the number of eggs
actually captured by the particular scenario may not be that large. These two
particular scenarios looked at non-commercially produced eggs, which account for a
very small portion of overall egg production.
The largest number of actual predicted illnesses was from scenario 4, where the
storage conditions for the eggs allowed the resolution of the YMT, and final use only
involved a moderate kill step. Thomas et al (2006) estimated that as many as 25%
of shell eggs in Australia are consumed after resolution of YMT, and although the risk
per serving was predicted to be 4 illnesses per million servings, because of the large
number of eggs captured by this scenario, it results in a prediction of 772 illnesses
each year when extrapolated to the current Australian population. Total numbers of
predicted illnesses from all scenarios was greater than 1800 cases per annum.
The final estimate for the level of illness was shown to be dependent on a number of
factors, namely:
•
the quality of hygienic practices on-farm (ie level and prevalence of
contamination with Salmonella)
•
hygienic practices during processing
•
time and temperature of egg storage (ie whether this allowed the resolution
of YMT and subsequent increase in levels of Salmonella in the egg)
•
end use of the eggs (level of cooking and subsequent reduction in
Salmonella)
The risk profile undertaken previously by the NSW Food Authority (Miles & Chan,
unpublished) identified that the significant control measures to manage
microbiological and chemical hazards were as follows:
Biosecurity measures on farm
Continued strict biosecurity measure will be necessary on commercial farms to
maintain the S. Enteritidis-free status. Because of the small number of breeder flocks
in Australia, and the already high level of biosecurity on these flocks, it is concluded
that the probability of a breeding flock becoming infected with S. Enteritidis is low.
However, should a breeding flock become infected and remain undetected, there
would be significant spread to a large number of layer flocks throughout Australia
(Arzey, 2002). If this should happen it is believed there would be significant increase
in the number of human cases of S. Enteritidis-related illness from eggs (Sergeant et
al, 2003), as has been observed in other countries where S. Enteritidis has become
endemic.
To ensure laying hens and breeding stock remain free from S. Enteritidis the
Australian egg industry has proactively initiated and developed various generic egg
quality Codes of Practice and food safety programs to manage relevant food safety
and quality risks at specific stages of the supply chain for both eggs and egg
products (AECL, 2005a; AECL, 2005b). However the uptake of these by industry is
voluntary. Through-chain regulatory control and implementation of food safety
controls and traceability on farm may aid in maintaining the S. Enteritidis-free status.
Page 131 of 189
Control measures for grading and processing of eggs and egg products
Higher risk operations, including grading and washing of eggs, handling and
processing of egg pulp, and processing of specialty duck eggs, should be carried out
with adequate control through the implementation of HACCP-based food safety
program. The revised Codex Code of Hygienic Practice for Eggs and Egg products
emphasises the use of the HACCP approach wherever appropriate to minimise food
safety hazards (Codex, 2006).
Pasteurisation of all liquid egg preparations should be monitored, recorded and
periodically verified. Monitoring should include evidence of the effectiveness of the
process.
Thomas et al (2006) stated that the epidemiological data shows that few foodborne
outbreaks in Australia can be attributed to the ingestion of clean intact shell eggs
that are produced under a quality control system, graded and retailed commercially.
Effective management of the supply chain
The time and temperature that eggs are stored at determines the length of time to
resolve the YMT. Resolution of the YMT can allow significant growth of Salmonella
within the egg, with Daughtry et al (2005) demonstrating that this was a significant
factor in increasing the risk of illness from egg consumption. While Thomas et al
(2006) estimated that 75% of eggs are consumed before the YMT is resolved,
management of the supply chain should ensure that a realistic shelf life is applied to
shell eggs, according to the expected storage conditions through the distribution,
wholesale and retail supply chain.
Prohibition on sale of cracked eggs
The Food Standards Code prohibits the sale of eggs with cracked shells unless those
eggs are sold for further processing. Crack detection forms a significant food safety
control for eggs, and as stated previously this should be undertaken with an
implemented food safety program in place. There is epidemiological evidence
pointing to the use of ungraded eggs and dirty, cracked/seconds eggs being sold
direct off-farm leading to outbreaks of salmonellosis. A requirement for egg farms to
notify of their operation to the NSW Food Authority would ensure greater ability to
trace back to the potential sources of foodborne illness.
Use of unpasteurised liquid egg preparations
Risk assessment work demonstrates that consumption of uncooked, or lightly cooked
foods containing raw eggs represent an increased risk for foodborne illness. Use of
unpasteurised liquid egg preparations, where sold, should be clearly identified as an
ingredient only for foods that will receive adequate heat treatment to destroy
Salmonella. Due to the potential for survival and growth of Salmonella serovars in
unpasteurised egg pulps, these are unsuitable for use in processed foods unless the
foods receives a sufficient heat treatment to ensure any Salmonella that may be
present are inactivated.
Food service to vulnerable populations
Epidemiological data from foodborne outbreaks consistently points to the use of raw
eggs in foods where it will not be well cooked, and/or the use of cracked and/or dirty
eggs in catering situations. Education of food service to vulnerable populations
should be undertaken on the risks of using raw eggs in foods or drinks that will not
be cooked. As an alternative, these institutions should look to use pasteurised egg
pulp that has been tested and certified as pathogen free.
Page 132 of 189
Conclusions
The risk assessment work undertaken on eggs and egg products consistently
demonstrates that Salmonella is the primary hazard of concern. This is clearly
evident from the epidemiological evidence from outbreaks around Australia where
eggs have been implicated as the vehicle.
However, prevalence data indicate that the use of clean intact eggs before the
resolution of YMT, and/or consumed either well cooked or used as an ingredient
where the egg will be well cooked should present very little risk to the consuming
public.
But with the number of outbreaks attributable to eggs appearing to increase in the
past few years, there continues to be issues with the management of hazards
throughout the egg supply chain. This risk assessment has identified a number of
areas that may, if not addressed through the implementation of appropriate control
measures, potentially contribute to the contamination of eggs and egg products with
Salmonella and lead to further increases in the outbreaks of foodborne illness
attributable to eggs. The development of a draft egg food safety scheme aims to
implement control measures across the egg supply chain to minimise further
foodborne illness attributable to eggs.
Page 133 of 189
References – Egg and egg products
January 2009, from
D460/$File/48040_1995.pdf
ABS [Australian Bureau of Statistics] (2000). Apparent Consumption of Foodstuffs, Australia,
1997-98 and 1998-99. ABS Cat no 4306.0. Retrieved 23 September 2011, from
http://www.abs.gov.au/AUSSTATS/[email protected]/0/123FCDBF086C4DAACA2568A90013939A?Ope
nDocument
ABS [Australian Bureau of Statistics] (2006). Value of Agricultural Commodities produced
2004-05. ABS Cat no 7503.0. Retrieved 13 January 2009, from
http://www.ausstats.abs.gov.au/ausstats/subscriber.nsf/0/758410C5AB68DCA9CA2571E6001
C8F0F/$File/75030_2004-05.pdf
AECL [Australian Egg Corporation Limited] (2005a). Code of Practice for shell egg,
production, grading, packing and distribution. Australian Egg Corporation Limited.
AECL [Australian Egg Corporation Limited] (2005b). Code of Practice for the manufacture of
Egg Products. Australian Egg Corporation Limited.
AFFA [Agriculture, Fisheries and Forestry Australia] (1999). Report on the National Residue
Survey 1998 Results, National Office of Food Safety, Department of Agriculture, Fisheries and
Forestry Australia, Canberra
AFFA [Agriculture, Fisheries and Forestry Australia] (2000). Report on the Australian National
Residue Survey Results 1999-2000. Agriculture, Fisheries and Forestry – Australia, Canberra.
ANZFA [Australia New Zealand Food Authority] (1999). Review of Microbiological Standards Egg and Egg Products. Australia New Zealand Food Authority, Canberra.
Arzey, G. (2002). Salmonella Enteritidis in Australia – Facts and fiction. Proceedings of Poultry
Information Exchange (PIX) 2002 pp 165-170
BRS [Bureau of Resource Science] (1996). Report on the National Residue Survey Results
1991-92 Results. Bureau of Resource Sciences, Canberra.
BRS [Bureau of Resource Science] (1998). Report on the National Residue Survey Results
1997 Results. Bureau of Resource Sciences, Canberra.
Codex (2006). Code of Hygienic Practice for Eggs and Egg Products. CAC/RCP 15. Codex
Alimentarius Commission.
Cox, J.M., Woolcock, J.B. & Sator, A.L. (2002). The significance of Salmonella, particularly
S. Infantis, to the Australian egg industry. Rural Industries Research and Development
Corporation (RIRDC) Web Publication W02/028. Retrieved 21 January 2009, from
http://www.aecl.org/Images/03-b%20The%20significance%20of%20Salmonella.pdf
Daughtry, B., Sumner, J., Hooper, G., Thomas, C., Grimes, T., Horn, R., Moses, A. & Pointon,
A. (2005). National food safety risk profile of eggs and egg products. A report for the
Australian Egg Corporation Limited (AECL) Publication No 05/06 Project SAR-47.
DAFF [Department of Agriculture, Fisheries and Forestry] (2003). National Residue Survey
Annual Report 2002-2003. Australian Government Department of Agriculture, Fisheries and
Forestry, Canberra.
Forestry, Canberra.
Page 134 of 189
Forestry, Canberra.
Forestry, Canberra.
Dawson, R.C., Cox, J.M., Almond, A. & Moses, A. (2001). Food Safety Risk Management in
Different Egg Production Systems. RIRDC Publication No 01/111.
Lin, C.-T.J., Morales, R.A. & Ralston, K. (1997). Raw and undercooked eggs: A danger of
salmonellosis. Food Review, January-April 1997, pp. 27-32. Retrieved 20 January 2009, from
http://www.ers.usda.gov/publications/foodreview/jan1997/jan97d.pdf
FSA [Food Science Australia] (2000). Final report – scoping study on the risk of plant
products. Food Science Australia prepared for SafeFood NSW.
FSANZ (2006). Initial Assessment Report – Proposal P301. Primary Production and Processing
Standard for Eggs and Egg Products. Food Standards Australia New Zealand, Canberra.
Humphrey, T.J. (1994). Contamination of egg shell and contents with Salmonella enteritidis: a
review. International Journal of Food Microbiology, 21, 31-40.
ICMSF [International Commission on Microbiological Specifications for Foods] (1998). Eggs
and egg products in Microorganisms in Foods 6. Microbial ecology of food commodities. (p.
475-520). Blackie Academic and Professional, London.
Jay, S., Davos, D., Dundas, M., Frankish, E. & Lightfoot, D. (2003). Salmonella. In Hocking,
A.D. (Ed.) Foodborne Microorganisms of Public Health Significance (pp. 207-266). Australian
Jones, D.R., Northcutt, J.K., Musgrove, M.T., Curtis, P.A., Anderson, K.E., Fletcher, D.L. &
Cox, N.A. (2003). Survey of Shell Egg Processing Plant Sanitation Programs: Effects on Egg
Contact Surfaces. Journal of Food Protection, 66,1486-1489
Lake, R. Hudson, A., Cressey, P. & Gilbert, S. (2004). Risk Profile: Salmonella (non-typhoidal)
in and on eggs. Institute of Environmental Science and Research Limited report prepared for
http://www.nzfsa.govt.nz/science/data-sheets/Salmonella-eggs.pdf
Lin, C.-T.J., Morales, R.A., & Ralston, K. 1997. Raw and undercooked eggs: The dangers of
Salmonellosis. Food Review, 20, 27-32.
McCreadie, K., Rizzo, J. & Keygan, M. (2007). Survey of specialty egg products in NSW.
Poster presented at Australian Institute of Food Science and Technology Convention –
Melbourne 2007.
McKellar, R.C. (1993). Effect of preservative and growth factors on secretion of listeriolysin O
by Listeria monocytogenes. Journal of Food Protection, 56, 380-384.
Miles, D. and Chan, C. (unpublished). Risk Profile and Risk Management of eggs and egg
products in NSW. NSW Food Authority report.
NEPSS [National Enteric Pathogen Surveillance Scheme] (2003). Non-human Annual Report
2002. Microbiological Diagnostic Unit, The University of Melbourne. National Enteric Pathogen
Surveillance Scheme report.
Papadopoulou, C., Dimitiou, D., Levidiotou, S., Gessouli, H., Panagiou, A., Golegou, S. &
Antoniades, G. (1997). Bacterial strains isolated from eggs and their resistance currently used
antibiotics: is there a health hazard for consumer? Comparative Immunology, Microbiology
and Infectious Diseases, 20:35-40
Sergeant, E.S.G., Grimes, T.M., Jackson, C.A.W., Baldock, F.C. & Whan, I.F. (2003).
Salmonella Enteritidis surveillance and response options for the Australian egg industry.
RIRDC Publication No 03/006.
Page 135 of 189
Thomas, C., Daughtry, B., Padula, D., Jordan, D., Arzey, G., Davey, K., Holds, G., Slade, J., &
Pointon, A.. (2006). An Egg: Salmonella Quantitative Risk Assessment Model. AECL
Publication
Todd, E. (1996). Risk Assessment of use of cracked eggs in Canada. International Journal of
Food Microbiology, 30, 125-143.
van Netten, P., van de Moosdijk, A., van Hoensel, P., Mossel, D.A.A. & Perales, I. (1990).
Psychrotrophic strains of Bacillus cereus producing enterotoxin. Journal of Applied
Bacteriology, 69, 73-79
Nations] (2002). Risk assessment of Salmonella in eggs and broiler chickens: Interpretive
summary. Retrieved 14 January 2009, from
www.who.int/foodsafety/publications/micro/salmonella/en/index/html
Page 136 of 189
Risk assessment – Conclusion
Risk is a function of the probability of a hazard occurring, multiplied by the severity
of the outcome. It is dependent on the food, the potential sources of contamination,
the hazard of concern, the type of processing, eventual use of the food product, and
the resulting illness. The latter can range from mild illness through to severe and life
threatening illnesses.
This risk assessment document provides a scientific review of the hazards and their
associated risks for food businesses covered by the food safety schemes of NSW
Food Regulation 2004. The document summarises the information from previous risk
assessments or risk profiles and supplements it with new and updated information as
available.
The review has illustrated that across the food safety schemes there are many
potential hazards that can impact on human health. In general, microbiological
hazards were considered the most significant, as chemical and physical hazards were
rarely detected in foods, or where chemical hazards were detected, they were at
levels that do not cause adverse health effects.
The review notes that mitigating the risk presented by such hazards involves a multifactorial approach that often extends beyond the controls implemented by a food
business operating under a food safety scheme of NSW Food Regulation 2004. The
implementation of control measures along the entire food chain, from on-farm
controls through to retail, is seen as being the most effective strategy for mitigating
risks.
It is concluded that for food businesses covered by the food safety schemes of NSW
Food Regulation 2004 mitigating food safety risks requires the development and
implementation of reliable, systematic and preventative procedures. Such procedures
are the core elements of food safety programs, which are either introduced due to
regulatory requirements or through industry sponsored Codes of Practice.
Page 137 of 189
Appendix 1: Microbiological and chemical hazards
of concern
This appendix provides additional information on selected microbiological and
chemical hazards, as a supplement to the information included the main part of this
risk assessment.
The information included in this appendix is limited to key points that have particular
relevance to the food commodities covered by the food safety schemes discussed in
previous chapters.
In-depth descriptions of the microbiological hazards and extensive reference lists are
available in the reference documents listed at the end of this appendix.
Page 138 of 189
Salm onella
Nature of the illness
Salmonellosis is one of the most important public and animal health disease
problems, causing worldwide morbidity and mortality of humans and animals.
Salmonellosis is a communicable disease readily transmissible from animals to man,
either directly or through contaminated products of plant or animal origin (Jay et al,
2003).
Gastroenteritis is caused by the penetration and passage of Salmonella cells from the
gut lumen into the epithelium of the small intestine where inflammation occurs.
Acute symptoms include nausea, vomiting, abdominal cramps, diarrhoea, fever and
headache. The onset time varies between 6–48 hours after consumption of
contaminated food. In some cases, chronic arthritis follows 3–4 weeks after the
onset of acute symptoms (FDA, 1992).
Salmonella serovars are important causes of gastrointestinal illness in humans.
Salmonella Enteritidis and S. Typhimurium are the most frequently reported non-
typhoidal serotypes in many countries and outbreaks have been associated with a
diverse range of food. However, a wide variety of serotypes have been associated
with outbreaks involving fresh produce. Although most Salmonella infections are selflimiting, in a small proportion of cases these may lead to bacteraemia. The case
fatality rate in industrialised countries is less than 1% (EU SCF, 2002).
The infective dose for causing foodborne salmonellosis in humans was, for decades,
believed to be high, that is 100,000 to one million cells. However, a number of
outbreaks have now occurred where the infective dose was found to be much lower,
for example <10–100 cells. This is particularly the case where products containing a
high fat level are involved, such as chocolate, cheese and salami (Bell & Kyriakides,
2002).
Associated foods
Salmonellosis has been associated with many foods including raw meats, poultry,
eggs, dairy products, fish, yeast, coconut, salad dressings, cake mixes, dried
gelatine, peanut butter, cocoa and chocolate (FDA, 1992).
Salmonella reside in the intestinal tract of infected animals. They are shed in the
faeces and can be readily transmitted to other animals or man. Most colonised
individuals become healthy excreters, resulting in contamination of the environment.
Contamination is spread amongst animals during transport, holding in confined
quarters and slaughter. Foods of animal origin become contaminated following faecal
contamination of the environment and equipment (ICMSF, 1996).
Table 48 is a recent history of common isolates of Salmonella from major animal
sources. Cross contamination is produced by contaminated raw foods during further
processing and preparation. Salmonella can also become established and multiply in
the environment and equipment of a variety of food-processing facilities (ICMSF,
1996).
Contamination of eggs, and particularly of egg contents, is believed to be a cause of
the large increase in human infections with S. Enteritidis in Europe and North
America since the 1980s. Contamination of intact eggs with S. Enteritidis is mainly
the result of infection of the hen’s reproductive system. Australia has been an
exception to the S. Enteritidis problem. Poultry and eggs in Australia have remained
free of S. Enteritidis (Jay et al, 2003).
Page 139 of 189
Table 48 – Top Salm onella serovars from major sources
Source
Human
Bovine
Porcine
Raw
meats
Ovine
Chicken –
broilers
Chicken –
layers
Eggs
2007
Number of isolates
Serovar & incidence
2185
Typhimurium 34.3%
Enteritidis 6.7%
313
Bovismorbificans 33.5%
Typhimurium 23.6%
Dublin 13.7%
118
Derby 27.1%
Johannesburg 16.9%
Typhimurium 10.2%
236
London 24.4%
Derby 22.9%
Stanley 13.6%
131
Typhimurium 44.3%
3842
II Sofia 33.8%
Typhimurium 14.8%
Infantis 10.2%
631
Typhimurium 17.3%
Virchow 13.3%
Mbandaka 10.5%
102
Typhimurium 30.4%
Agona 12.7%
Anatum 10.8%
2006
Number of isolates
Serovar & incidence
1792
Typhimurium 34.3%
280
Typhimurium 30.4%
Dublin 10.0%
226
Derby 51.3%
London 11.9%
Johannesburg 10.2%
98
Heidelberg 29.6%
Chester 7.1%
297
Typhimurium 39.4%
4386
II Sofia 43.3%
Typhimurium 16.2%
Infantis 6.6%
791
Mbandaka 20.9%
Typhimurium 15.8%
Agona 10.7%
63
Anatum 36.5%
Montevideo 19.0%
Ohio 19.0%
2005
Number of isolates
Serovar & incidence
1713
Typhimurium 34.3%
Enteritidis 8.8%
293
Typhimurium 23.9%
Dublin 10.9%
208
Infantis 34.1%
Derby 23.6%
Anatum 13.0%
501
Johannesburg 29.1%
London 15.2%
Derby 13.4%
66
Typhimurium 31.8%
6011
II Sofia 49.8%
Infantis 11.1%
Typhimurium 7.8%
364
Typhimurium 13.5%
Kiambu 11.8%
Mbandaka 10.4%
84
Typhimurium 38.1%
Anatum 22.6%
Singapore 10.7%
adapted from Australian Salmonella Reference Centre 2007 Annual Report (Davos, 2007)
Table 49 – Characteristics of Salm onella
Minimum
Optimum
Maximum
Temperature (°C)
5.2*
35–43
46.2
pH
3.8
7–7.5
9.5
aw
0.94
0.99
>0.99
Limits for growth of Salmonellae when other conditions are near optimum
* Most serotypes fail to grow at <7°C
Survival in food
Survive for long periods in foods — 10 weeks in butter, 28 days in
refrigerated vegetables and very stable in chocolate
Survival in
Survive well on ceramic, glass and stainless steel surfaces. Survive on
environment
human skin. Can become established and multiply in a food processing
environment, where they become a source of contamination
Controls
• A kill step, such as cooking, to assure destruction of Salmonellae in
contaminated foods, especially raw meats
• Prevention of contamination (cross contamination) of RTE foods,
including good personal hygiene and exclusion of ill food handlers
• Low or high temperature storage of foods to prevent growth
• Control of contamination in food processing areas
adapted from ICMSF (1996)
Page 140 of 189
Campylobacter
Campylobacter is now recognised as an important enteric pathogen with OzFoodNet
data showing that campylobacteriosis is the major cause of notified food poisononing
in Australia (despite the fact it is not a notifiable infection in NSW). Surveys have also
shown that Campylobacter jejuni is the leading cause of bacterial diarrhoea in the
USA. It causes more illness than Shigella spp. and Salmonella serovars combined
(FDA, 1992). Symptoms of campylobacteriosis (also known as campylobacter
enteritis or gastroenteritis) often include fever abdominal pain, nausea, headache,
and muscle pain as well as diarrhoea. The illness usually occurs 2–5 days after
ingestion of the contaminated food or water. Illness generally lasts 7–10 days but
relapses are not uncommon, occurring in about 25% of cases (FDA, 1992).
Complications are relatively rare, but infections have been associated with reactive
arthritis, haemolytic uraemic syndrome, and following septicaemia, infections of
nearly any organ. Meningitis, recurrent colitis, acute cholecystitis and Guillain-Barré
syndrome are very rare complications (FDA, 1992).
Associated foods
Campylobacter frequently contaminates raw chicken, with surveys showing that 20–
100% of raw retail chickens are contaminated. Raw milk is also a source of
infections. The bacteria are often carried by healthy cattle and by flies on farm. Nonchlorinated drinking water may also be a source of infections.
Campylobacter from raw meat may contaminate work areas and the hands of kitchen
staff before being transferred to RTE foods or causing self-infection.
Raw milk was the most frequently reported vehicle in food related outbreaks of
Campylobacter (Wallace, 2003; ICMSF, 1996). Those references also noted evidence
that sporadic (as opposed to outbreak) illness was linked to poultry consumption. A
more recent case-control study of Campylobacter infection found that consumption
of chicken at restaurant was the largest attributable factor, followed by consumption
of non-poultry meat at a restaurant (Friedman et al, 2004).
Table 50 – Characteristics of Cam pylobacter
Minimum
Optimum
Maximum
Temperature (°C)
32
42–43
45
pH
4.9
6.5–7.5
~9
aw
>0.987
0.997
Limits for growth of Campylobacter when other conditions are near optimum
The organisms are do not tolerate high levels of oxygen and grow best with 5-6% oxygen
and 10% carbon dioxide
Survival in food
Growth usually does not occur in foods due to the minimum
temperature requirement not being met. The organism is relatively
fragile and is inactivated by oxygen, drying, heating, disinfectant
and acid conditions. Despite declining numbers, the organism does
survive in moist foods for variable lengths of time
Survival in
Survival on surfaces is prolonged by blood and the fluid obtained
environment
from the thawing of frozen meat
Controls
• A kill step, such as cooking, to assure destruction of
Campylobacter in contaminated foods, especially raw meats
and raw milk
• Prevention of contamination (cross contamination) of RTE foods
• Prevention of infection of flocks has been proposed as a control
measure
Page 141 of 189
Some strains of Staphylococcus aureus are capable of producing a highly heat stable
protein toxin that causes illness in humans. Onset of symptoms of food poisoning
occurs between 1 and 7 (usually 2–4) hours after the ingestion of food containing
staphylococcal enterotoxins. The most common symptoms are nausea, vomiting,
retching, abdominal cramps and diarrhoea. In severe cases, headache and collapse
may occur. Recovery is rapid, usually within two days (ICMSF, 1996).
A toxin dose of less than 1.0 microgram in contaminated food will produce symptoms
of staphylococcal intoxication. This toxin level is reached when S. aureus populations
exceed 100,000 per gram (FDA, 1992).
Associated foods
Foods that require considerable handling during preparation and that are kept at
slightly elevated temperatures after preparation are frequently involved in
staphylococcal food poisoning. Frequently implicated foods include meat and meat
products; poultry and egg products; salads such as egg, tuna, chicken, potato and
macaroni; bakery products such as cream-filled pastries, cream pies and chocolate
éclairs; sandwich fillings; and milk and dairy products.
Staphylococci are wide-spread in the environment. Humans and animals are the
primary reservoir. Staphylococci are present in the nasal passages and throats and
on the hair, and skin of 50% or more of healthy individuals. Although food handlers
are the main source of food contamination in food poisoning outbreaks, equipment
and environmental surfaces can also be sources of contamination with S. aureus
(FDA, 1992).
Table 51 – Characteristics of Staphylococcus aureus
Growth
Growth
Toxin
Toxin Range
Optimum
Range
Optimum
Temperature (°C)
37
7–48
40–45
10–48
pH
6–7
4–10
7–8
4.5–9.6
aw
0.98
0.83->0.99
0.98
0.87->0.99
Limits for growth and toxin production for S. aureus when other conditions are near optimum
and aerobic
Survival in food
Bacteria are easily killed by heat but are salt tolerant and resistant
to drying and can survive for extended periods in food. The toxins
are very resistant to heat and will survive cooking
Survival in environment
Bacteria survive well under most environmental conditions and can
persist for some time in food-production areas
Controls
• Protect foods from contamination
• Avoid conditions (mainly temperatures) where S. aureus
growth can occur
• For products such as salami and cheese that are held at
temperatures where S. aureus can grow, it is very important
to exercise control over the raw materials as well as the
fermentation and maturation stages
Page 142 of 189
Clostridium perfringens
Food poisoning caused by Clostridium perfringens continues to be an important
cause of morbidity in the community. Large outbreaks are still common in Australia
(Bates & Bodnaruk, 2003). Spores of the organism persist in soil, sediments, and
areas subject to human or animal faecal pollution. From the natural environment it is
easily spread to foods. All foods are considered potential sources of the organism,
however according to Bates & Bodnaruk (2003) only about 2–5% of C. perfringens
isolated from food and animals produce C. perfringens enterotoxin (CPE).
The common form of perfringens food poisoning is characterised by intense
abdominal cramps and diarrhoea which begins 8–22 hours after consumption of
foods containing large numbers of C. perfringens. More than 108 vegetative cells are
required and the strain of C. perfringens must be capable of producing the food
poisoning toxin. This illness is a food infection or toxicoinfection only one episode has
ever implied the possibility of intoxication (ie illness from preformed toxin). Toxin
production occurs in the digestive tract and is associated with sporulation (FDA,
1992).
Associated foods
Diarrhoea due to C. perfringens is most commonly associated with the consumption
of cooked, uncured meat products that have been cooled slowly or stored under
inadequate refrigeration and then consumed without thorough reheating.
C. perfringens is commonly found on all meats, but in relatively low numbers. It is
largely derived from the intestines of the animal. C. perfringens produces a spore
which helps it survive harsh environmental conditions. The spores of food poisoning
strains are more heat resistant and can survive cooking.
Table 52 – Characteristics of Clostridium perfringens
Minimum
Optimum
Maximum
Temperature (°C)
12
43–47
50
pH
5.5–5.8
7.2
8.0–9.0
aw
0.93*
0.95-0.96
Limits for growth of C. perfringens when other conditions are near optimum
* Reports vary depending on the humectant
Survival in food
The bacterial spore survives well in food
Survival in
C. perfringens is widely distributed in the environment where it
environment
survives well. It frequently occurs in the intestines of humans and
many domestic and feral animals
Controls
• Control relies almost entirely on cooking and cooling
procedures. An effective control measure is to cool the product
rapidly, particularly through the temperature range 55 to 15°C
• Vegetative cells are readily killed by heat and an effective
reheating process will ensure that large numbers of vegetative
cells are not consumed
Page 143 of 189
Bacillus cereus
Foodborne illnesses associated with Bacillus cereus may occur as two distinct
syndromes: diarrhoeal and emetic. The diarrhoeal illness has a typical incubation
period of 10–13 hours. The gastroenteritis is usually mild with abdominal cramps,
profuse watery diarrhoea, rectal spasms and moderate nausea, usually without
vomiting. Evidence indicates that diarrhoeal illness is caused by the consumption of
moderate to high numbers of organisms and production of toxin in the gut.
The emetic illness usually has an onset from 1–5 hours after consuming the
implicated food. Acute nausea and vomiting are the major symptoms with diarrhoea
being uncommon. The symptoms of the emetic syndrome are toxin mediated. The
emetic toxin is a heat stable peptide that appears to be produced when B. cereus
grows on particular substrates such as those containing starch or other farinaceous
materials (Jenson & Moir, 2003).
Associated foods
A wide variety of foods including meats, milk, vegetables and fish have been
associated with the diarrhoeal type food poisoning. The vomiting type outbreaks
have generally been associated with rice products, however other starchy foods such
as potato, pasta and cheese products have also been implicated. Food mixtures such
as sauces, puddings, soups, casseroles, pastries, and salads have frequently been
incriminated in food poisoning outbreaks (FDA, 1992).
Every well-documented report of B. cereus intoxication has described time and
temperature abuse that allowed relatively low (innocuous) levels of B. cereus in
foods to greatly increase.
Table 53 – Characteristics of Bacillus cereus
Minimum
Optimum
Maximum
Temperature (°C)
4
30–40
55
pH
5.0
6.0–7.0
8.8
aw
0.93
Limits for growth of B. cereus when other conditions are near optimum
Survival in food
The bacterial spore survives well in food including cooked foods
Survival in
B. cereus is widely distributed in nature. It is readily isolated from
environment
soil, dust, cereal crops, vegetation, animal hair, fresh water and
sediments. Consequently, it is not surprising to find the organism
on virtually every raw agricultural commodity
Controls
• Prevention of illness requires the control of spore germination
and the growth of vegetative cells in cooked RTE food. Cell
multiplication during inadequate cooling of cooked cereal-based
or protein-containing foods is a major concern
• Food to be stored should be cooled rapidly to a temperature
that prevents the growth of B. cereus
• Food that is to be held warm should be maintained above 60°C
• Once formed in a food the emetic toxin is heat stable and can
withstand normal cooking or reheating temperatures
Page 144 of 189
Listeria m onocytogenes
Foodborne listeriosis presents in three ways (Sutherland et al, 2003):
•
Infection during pregnancy acquired following the consumption of food
contaminated with Listeria monocytogenes. This is a mild flu-like illness or
asymptomatic in the mother but with serious implications for unborn infants
including spontaneous abortion, foetal death, stillbirth and meningitis.
Infection is more common in the third trimester.
•
Infection of non-pregnant adults acquired following the consumption of
contaminated food. Asymptomatic or mild illness which might progress to
central nervous system infection such as meningitis. Most common in the
immunocompromised or elderly.
•
Listeria food poisoning following consumption of food with exceptionally high
levels of L. monocytogenes (>107/g). Vomiting and diarrhoea, sometimes
progressing to bacteraemia but usually self resolving.
The onset time to serious forms of listeriosis is unknown but may range from a few
days to three weeks. The onset time to gastrointestinal symptoms is unknown but is
probably greater than 12 hours. When listeric meningitis occurs, the overall mortality
may be as high as 70% from septicaemia 50% from perinatal/neonatal infections
greater than 80%. The mother usually survives infections during pregnancy (FDA,
1992).
Lake et al (2005) comments that it is becoming increasingly realised that the only
completely safe dose of L. monocytogenes is zero, even in healthy people. However,
the probability of invasive disease following exposure to even moderate levels of cells
is very low. The probability of illness for a given dose is about 100 times higher for
‘at risk’ populations (the elderly, the immunocompromised and the perinatal). The
dose response model used by Lake et al (2005) for a significant L. monocytogenes
dose of 106 cells generates probabilities of illness of about 10-6 for the ‘more at risk’
and approaching 10-8 for the general population. When compared with probabilities
of illness in generated in the FDA/USDA (2003) risk assessment on RTE foods, this
appears to be a conservative.
Associated foods
L. monocytogenes has been associated with such foods as raw milk, supposedly
pasteurised milk, cheese (particularly soft-ripened varieties), ice-cream, raw
vegetables, fermented raw meat sausages, raw and cooked poultry, raw meats and
raw and smoked fish. Its ability to grow at low temperatures permits multiplication in
refrigerated foods.
The vast majority of cases are sporadic, making epidemiological links to food very
difficult.
Page 145 of 189
Table 54 – Characteristics of Listeria m onocytogenes
Minimum
Optimum
Maximum
Temperature (°C)
-0.4*
37
45
pH
4.39
7.0
9.4
aw
0.92
Limits for growth of L. monocytogenes when other conditions are near optimum
* Growth can occur in a variety of foods at normally encountered refrigeration temperatures
Survival in food
L. monocytogenes is quite hardy and resists the deleterious effects of
Survival in
environment
Listeria have been isolated from a wide variety of habitats, including soil,
Controls
freezing, drying and heat remarkably well for a bacterium that does not
form spores
silage, sewage, and food-processing environments. Wet surfaces in foodprocessing plants often harbour listeriae and this, combined with the
ability of listeriae to grow at low temperatures, is reflected in their
occurrence in refrigerators and on chilling units. Owing to the prevalence
of L. monocytogenes in raw materials and its ability to multiply in the
environment of many food-processing, traditional cleaning and
disinfection methods, equipment design and management practices may
be inadequate or even impair the control of L. monocytogenes
The prevention of human listeriosis begins at the farm and continues
through processing to the selection and handling of food by the
consumer. A complete diet that is free of L. monocytogenes is impossible
to obtain. However, the application of farm-to-consumer controls can
reduce the risk of foodborne listeriosis
On farm:
Silage should be rapidly acidified to pH <4.0 to prevent the development
of high numbers of L. monocytogenes. This is particularly important for
use on dairy farms where milk could be used for raw milk cheeses
In processing:
• Minimise the growth of L. monocytogenes in raw materials,
particularly before and during the processing of raw foods
• Where possible use listericidal processes to assure the destruction of
•
L. monocytogenes
Minimise the risk of recontamination of RTE foods that are further
processed after receiving a listericidal treatment through
environmental controls and GMP
Storage:
• Storage at 5°C or below will retard, but not prevent, multiplication in
many food products
Retail:
• Separate raw food of animal origin from RTE foods
• Use an effective method, at appropriate intervals, of disinfecting
slicing equipment and display cases
• Maintain proper storage and display temperatures and monitor ‘useby’ and ‘best before’ dates
Consumers:
The risk of foodborne listeriosis is much greater among persons with
reduced immunity (eg pregnant women, persons with malignant disease
or AIDS) and patients with certain underlying illnesses (eg heart disease,
diabetes, renal disease). These groups should follow published advice on
the selection and handling of foods to reduce the risk of listeriosis
Page 146 of 189
Vibrio parahaem olyticus
Pathogenic and non-pathogenic forms of Vibrio parahaemolyticus can be isolated
from marine and estuarine environments and from fish and shellfish dwelling in these
environments.
Gastroenteritis is the most common clinical syndrome caused by
V. parahaemolyticus. The infectious dose for healthy individuals, recorded in
outbreaks, is about 105 to 109 viable cells and results in an acute illness, following a
short incubation period of between 4–30 hours. The major symptoms include
diarrhoea which can be bloody, abdominal pain, nausea, and vomiting. Usually
gastroenteric infections remain in the gut and are self-limiting however, a death due
to V. parahaemolyticus following the consumption of oysters was reported in NSW in
1992 (Desmarchelier, 2003). The infectious dose may be markedly lowered by the
coincident consumption of antacids (FDA, 1992).
Associated foods
Infections with this organism have been associated with the consumption of raw,
improperly cooked, or cooked and recontaminated fish and shellfish. A correlation
exists between the probability of infection and the warmer months of the year.
Improper refrigeration of seafood contaminated with this organism will allow its
proliferation, which increases the probability of infection.
A pandemic strain of V. parahaemolyticus O3:K6 has caused epidemics in South-east
Asia and North America since 1995. In Australia, sporadic cases occasionally occur
and these often have a recent history of overseas travel (Desmarchelier, 2003).
Serotype O3:K6 and its serovariants are undergoing global spread (Balakrish Nair et
al, 2007). The organism could arrive in Australia in ballast water, imported seafood
or carried by a traveller. International evidence suggests that domestic foodborne
illness could result.
Other Vibrio spp. of concern include Vibrio cholerae and Vibrio vulnificus. There is a
risk associated with imported seafood and travellers arriving from countries where
cholera is endemic.
V. vulnificus is found in Australia and there have been rare episodes of foodborne
illness. The controls listed above for V. parahaemolyticus are effective against
V. vulnificus. There is a strong association between V. vulnificus infection and
patients with underlying chronic conditions including liver disease, malignancy and
increased serum iron levels. Avoidance of raw seafood is recommended in these
cases.
Page 147 of 189
Table 55 – Characteristics of Vibrio parahaem olyticus
Optimum
Range
Temperature (°C)
37
5–43
pH
7.8–8.6
4.8–11
aw
0.981
0.940–0.996
Salt (%)
3
0.5-10
Limits for growth of V. parahaemolyticus when other conditions are near optimum
Survival in food
V. parahaemolyticus die when exposed to temperatures below
5–7°C the rate of mortality is highest between 0–5°C. The
organisms are only moderately sensitive to freezing and will
persist in frozen seafoods for long periods
The number of culturable V. parahaemolyticus in water is directly
related to temperature and the organisms are rarely isolated
when water temperatures are <15°C. The apparent
disappearance of vibrios in the aquatic environment when
conditions are suboptimal may be explained in part by the ability
of the organisms to enter a dormant or viable but non-culturable
state. Associations between vibrios and higher organisms and
animals play a significant environmental role for vibrios and may
be protective during adverse conditions
Controls
•
The primary control measure is to prevent multiplication of
the organism after harvesting and this is most readily
achieved by chilling seafoods to <5°C and holding them
under refrigeration. Since temperatures are maintained in the
range 0–5°C in fish storage and distribution systems this may
considerably reduce the risk. (Note that live bivalve molluscs
have differing storage requirements)
•
Cooking to an internal temperature of >65°C will effectively
destroy V. parahaemolyticus
•
Cross contamination of cooked foods, such as crabs or
prawns, should be avoided by strict separation of raw and
cooked products and by preventing transfer via containers or
shared surfaces or by employees preparing both raw and
cooked products
Page 148 of 189
Shigella species
Shigellosis is principally a disease of humans and rarely occurs in animals. Most cases
of shigellosis result from the ingestion of faecally contaminated food or water. The
major contribution to contamination of food is poor personal hygiene of food
handlers.
The illness is caused when virulent Shigella organisms attach to, and penetrate,
epithelial cells of the intestinal mucosa. Some strains produce endotoxin and Shiga
toxin (very much like the verotoxin of E. coli O175:H7). After invasion, they multiply
intracellularly and spread to contiguous cells resulting in tissue destruction.
Symptoms include abdominal pain cramps diarrhoea fever vomiting blood, pus or
mucous in stools and tenesmus. The onset time is from 12 to 50 hours.
Infections are associated with mucosal ulceration, rectal bleeding and drastic
dehydration. The fatality rate may be as high as 10–15% with some strains. Reiter’s
disease, reactive arthritis and haemolytic uremic syndrome are possible sequelae that
have been reported following shigellosis.
Associated foods
A variety of foods have been associated with shigellosis. Faecal contamination of
water and unsanitary handling by food handlers are the most common cause.
Table 56 – Characteristics of Shigella spp.
Minimum
Maximum
Temperature (°C)
6.1
47.1
pH
4.9
9.34
S. sonnei
Salt (%)
5.18
S. flexneri
Temperature (°C)
7.9
45.2
pH
5.0
9.19
Salt (%)
3.78
Limits for growth of Shigella when other conditions are near optimum
Survival in food
Shigellae survive in a wide range of foods
On inanimate surfaces shigellae survive well between -20°C and
37°C
Controls
•
Contamination can be prevented or minimised by using clean
utensils instead of hands. Control is achieved by good
personal hygiene and hand washing prior to working with
food is most important
•
Cooked foods should not be touched with the hands
•
Persons who are ill should be excluded from areas where
food is prepared
Page 149 of 189
Escherichia coli
Escherichia coli is a normal non-pathogenic and useful inhabitant of the bowel. There
are a minority of enterovirulent strains within the species that cause illness ranging
from travellers’ diarrhoea through to a destructive and, not uncommonly, fatal
illness. Enterohaemorrhagic E. coli (EHEC) are associated with ‘hamburger disease’ in
the USA and the Garibaldi outbreak in Australia. EHEC produce potent toxins known
as Shiga toxins which are toxic to cultured Vero cells (thus the abbreviations STEC
and VTEC) and other toxic factors.
The illness caused by EHEC is called haemorrhagic colitis. It is characterised by
severe cramping and diarrhoea which is initially watery but becomes grossly bloody.
Occasionally vomiting occurs. Fever is usually low grade or absent. The illness is
usually self limiting and lasts for an average of eight days.
Some victims, particularly the very young, have developed haemolytic uraemic
syndrome (HUS), which is characterised by renal failure and haemolytic anaemia.
From 0–15% of haemorrhagic colitis victims may develop HUS. The illness can lead
to permanent loss of kidney function.
In the elderly, HUS with fever and neurologic symptoms constitute thrombotic
thrombocytopenic purpura. This illness can have a mortality rate in the elderly as
high as 50% (FDA, 1992).
Associated foods
Undercooked or raw hamburger mince has been implicated in many of the
documented US EHEC outbreaks. However, E. coli O157:H7 outbreaks have
implicated alfalfa sprouts, unpasteurised fruit juices, dry-cured salami, lettuce, game
meat and cheese curds. Raw milk was the vehicle in a school outbreak in Canada
(FDA, 1992). Other EHEC strains include O26, O111, O103, O121, O45 and O145.
Humans are believed to be the major, if not the only, source for most of the
enterovirulent E. coli that cause human illness. Infected food handlers can
contaminate food. Humans may also be carriers of EHEC strains.
However, the major reservoirs of a number of important STEC strains that infect
humans are the intestinal tract of ruminants such as cattle and sheep (Desmarchelier
& Fegan, 2003).
Page 150 of 189
Table 57 – Characteristics of pathogenic Escherichia coli
Minimum
Optimum
Maximum
Temperature (°C)
~ 7-8
35-40
~ 44–46
pH
4.4
6–7
9.0
aw
0.95
0.995
Limits for growth of E. coli when other conditions are near optimum
Survival in food
Pathogenic E. coli generally survive well in refrigerated foods and in
frozen ground beef. EHEC may survive for long periods in
fermented or acid foods
Survival in
E. coli is capable of growth in food and on inadequately cleaned
environment
surfaces associated with food processing. It can also become
established in food processing plants (Desmarchelier & Fegan,
2003). Pathogenic E. coli have no unique resistance to chlorine
Controls
• Hygienic practices during slaughter
• Protect vegetable crops from manures and untreated sewage
effluent
• Rapidly cool carcases after slaughtering and processing
• Use safe food handling techniques and proper personal hygiene
to avoid contamination of RTE foods
• Properly heat foods to kill pathogens and hold food at
appropriate temperatures
• Do not use un-chlorinated water for cleaning food-processing
equipment or food contact surfaces
• Avoid raw and partially cooked meats and unpasteurised milk
Foodborne botulism is a severe type of food poisoning caused by ingestion of foods
containing the potent neurotoxin formed during the growth of the organism. As little
as 30 ng of neurotoxin is sufficient to cause illness and even death. The toxin is heat
labile and can be destroyed if heated at 80°C for 10 minutes or longer. The incidence
of illness is low but is of considerable concern because of its high mortality rate if not
treated immediately and properly. Limiting the pathogen’s growth in foods is
important for public health.
Onset of symptoms in foodborne botulism is usually 18 to 36 hours after ingestion of
food containing the toxin, although cases have varied from four hours to eight days.
Early signs of intoxication consist of marked lassitude, weakness and vertigo followed
by double vision and progressive difficulty in speaking and swallowing. Difficulty in
breathing, weakness in other muscles, abdominal distension and constipation may
also be common symptoms.
Foodborne botulism is primarily associated with two physiologically and genetically
distinct anaerobic bacteria, proteolytic C. botulinum and non-proteolytic
C. botulinum. Proteolytic C. botulinum is a mesophile, while non-proteolytic
C. botulinum is a psychrotroph that grows and forms toxin at 3°C. With an ability to
grow at chill temperatures, non-proteolytic C. botulinum is the principal
microbiological safety concern, in relation to spore-forming bacteria, in the
manufacture of chilled foods (Peck et al, 2008).
Associated foods
Any food that is conducive to outgrowth and toxin production, that when processed
allows spore survival and is not subsequently heated before consumption can be
Page 151 of 189
associated with botulism. Almost any type of food that is above pH 4.6 can support
the growth and toxin production by C. botulinum.
Botulism toxin has been isolated in a considerable variety of foods such as canned
corn, peppers/capsicum, green beans, soups, beets, asparagus, mushrooms, ripe
olives, spinach, tuna, chicken and chicken livers and liver pâté, luncheon meats,
ham, sausage, stuffed eggplant, lobster, smoked and salted fish and chopped garlicin-oil (FDA, 1992).
Refrigerated processed foods of extended durability (REPFEDS) are of concern as
some strains of C. botulinum grow and form toxin at refrigeration temperatures
(Szabo & Gibson, 2003).
Peck et al (2008) reviewed data from 1307 independent challenge tests. The results
from some of those tests demonstrate that non-proteolytic C. botulinum, if present,
is able to form toxin in certain foods and materials at <10°C within 10 days. At 8°C,
100/514 (19.5%) independent challenge tests were positive for toxin by day 10,
while at 4–7°C only 5/387 (1.3%) tests were positive. The products that were
positive for toxin by day 10 were mainly fish and meat products. One cooked
vegetable food was also positive.
Peck et al (2008) noted that 1010 prepared chilled meals have been produced in the
UK over the last two decades. In that time no reports could be identified of
foodborne botulism associated with correctly stored commercial chilled food. They
attribute the lack of botulism to one or more ‘unquantified controlling factors’ (eg
raw material quality, heats process that damage spores, high hygiene during
manufacture, good chill chain) and note the need for better understanding of the
controlling factors.
Table 58 – Characteristics of Clostridium botulinum
Proteolytic C. botulinum
Minimum
Optimum
Maximum
Temperature (°C)
10
45-50
pH
4.6
aw
~ 0.94
Non-proteolytic C. botulinum
Minimum
Optimum
Maximum
Temperature (°C)
3.3
40-45
pH
5.0
aw
~ 0.97
Limits for growth of C. botulinumwhen other conditions are near optimum
C. botulinum produces heat resistant spores and grows in the absence of oxygen
Survival in food
Spores survive well in foods. Also survive normal cooking
temperatures
Survival in
C. botulinum is ubiquitous and survives well in a wide variety of
environment
environmental conditions
Controls
• Retort low acid canned food correctly. Outbreaks are mostly
reported with home canned products and rarely with
commercial products following a formulation change
• Ensure all components of high acid foods and acidified foods
are below pH 4.6
• Include additional hurdles to Clostridial growth or limit shelf life
of products on RTE chilled foods
adapted from ICMSF (1996); Szabo & Gibson (2003)
Page 152 of 189
Yersiniosis is frequently characterised by such symptoms as gastroenteritis with
diarrhoea and/or vomiting however, fever and abdominal pain are the hallmark
symptoms. Yersinia infections mimic appendicitis and mesenteric lymphadenitis, but
the bacteria may also cause infections of other sites such as wounds, joints and the
urinary tract.
Illness onset is usually 24–48 hours after the ingestion of food or drink. The major
‘complication’ is the performance of unnecessary appendectomies, since one of the
main symptoms of infections is abdominal pain in the lower right quadrant. Reactive
arthritis occurs in 2–3% of cases bacteraemia and diffuse disease occur rarely (FDA,
1992).
Associated foods
Strains of Yersinia enterocolitica can be found in pork, beef, lamb, oysters, fish and
raw milk, however not all serotypes carry the plasmid encoding the virulence factors
for pathogenicity (Barton & Robins-Brown, 2003). The exact cause of food
contamination is unknown. However, the prevalence of this organism in soil, water
and in animals offers ample opportunities for it to enter the food supply. Pigs are
believed to be the principal reservoir of bioserotypes pathogenic to humans (ICMSF,
1996).
Table 59 – Characteristics of Yersinia enterocolitica
Maximum
42
Growth at 9.6
No Growth at 10
NaCl (%)
Growth at 5
No Growth at 7
Limits for growth of Y. enterocolitica when other conditions are near optimum
Survival in food
Y. enterocolitica is quite resistant to adverse storage conditions.
Since it capable of multiplying at very low temperatures,
refrigerated storage may not be a reliable means of preventing
foodborne illness
Survival in
The organism survives well in water and soil. The major reservoir is
environment
the live pig
Controls
• Reduction in contamination of pig carcases can be achieved by
changes in pig slaughtering procedures (Barton & RobinsBrowne, 2003)
• Proper handling of raw pork when preparing food in foodservice establishments and the home. Especially separating raw
pork from RTE foods
Temperature (°C)
pH
Minimum
-1.3
4.2
Optimum
25–37
7.2
Page 153 of 189
Cronobacter sakazakii (formerly classified as Enterobacter sakazakii) has been
associated with neonatal meningitis, necrotising enterocolitis, bacteraemia and
necrotising meningoencephalitis. Reported mortality rates are high 10–55% for
necrotising enterocolitis and 40-80% for meningitis in neonates.
Invasive C. sakazakii illness is not a common occurrence in infants. Approximately 60
cases were reported between 1958 and 2008. However, there is concern that it has
been underreported. Studies estimate the annual rate of invasive C. sakazakii to be 1
per 100,000 children under 12 months old and 9.4 per 100,000 in very low birth
weight infants.
Meningitis tends to be associated with near-term infants of normal birth weight
where infection occurred soon after birth. Bacteraemia tends to be associated with
pre-term infants of very low birth weight where infection occurs in the first two
months of life (FSAI, 2007).
C. sakazakii has been isolated from many foods and environmental sources and can
be considered to be ubiquitous. The role of these sources in neonatal infection has
not been determined. However, infection studies provide evidence of the role of
powdered infant formula:
•
Eight cases cite infant formula as the suspected cause with the source
unknown or not specified in the other 19 cases
•
In 26 cases where feeding patterns were specified 24 were fed on powdered
infant formula 15 of the formula samples yielded C. sakazakiiin 13 of the
cases the clinical and formula strains were indistinguishable (Bowen &
Braden, 2006)
C. sakazakiihas been isolated from infant formula milk powder on many occasions,
although contamination can be considered as low and sporadic.
A number of control measures are emerging (FSAI, 2007):
•
Tight microbiological specifications on powdered infant formula
•
The use of recommended procedures for the preparation of formula
•
Limitations on ‘hang times’ for prepared formula
•
The use of commercially sterilised ready-to-feed formula in some
circumstances
Page 154 of 189
Parasitic protozoa and worms
Foodborne infections due to parasites have been known since ancient times, and
continue to be of great importance in many regions of the world (ICMSF, 1996).
Some may be confined to tropical regions for climatic reasons. Others are world-wide
in distribution, although they are more often found at a higher level of prevalence, in
such areas as Third World countries, being associated with conditions of poor
sanitation and hygiene.
While some parasitic diseases may be a significant cause of human mortality, most
cause chronic illness and are associated with high levels of morbidity, especially in
the developing countries of the world.
Parasites may be involved with food in a number of ways:
•
They may directly contaminate food or water, mainly through direct or
indirect faecal contamination of the soil or via infected food handlers
•
They may contaminate invertebrates which are eaten as food or accidently
ingested on salads
•
They may infect food animals comprising a direct part of their life cycle as an
intermediate host (or as a transfer or transport host where no development
occurs) and which infects the human host when the meat is eaten (Goldsmid
et al, 2003)
Many of the strategies used to control foodborne parasites are commonplace in
Australia. General sanitation levels are high, water quality is good, community
infection rates are low and meat inspection is required. Manure control and effluent
reuse are possible issues.
Viruses
Hepatitis A and viral gastroenteritis are the only viral diseases that have been
regularly shown in recent years to be foodborne. Foodborne viral gastroenteritis is
commonly caused by members of the small, round, structured viruses group, the
best known being Norovirus (formerly classified as Norwalk and Norwalk-like
viruses).
The human body is the only ultimate source of the contamination by the human
enteric viruses discussed here. The viruses are shed in large quantities in the faeces
of infected persons for a period varying from a few days to several weeks.
Contamination of food occurs only through direct (eg food handlers) or indirect (eg
environmental) faecal contamination.
Two general types of food have been dominant amongst reports of viral
contamination: bivalve molluscs harvested from polluted waters and foods prepared
by infected food handlers and not subsequently cooked. Contamination of food by
infected food handlers is attributed to poor personal hygiene.
Bivalve molluscs feed by filtering large volumes of surrounding water in order to trap
suspended particles. Bivalves can contain human enteric viruses and increase their
concentration to a higher level than that in water. Viruses are introduced into
watercourses and coastal waters by the routine discharge of treated and untreated
domestic sewage and by runoff from land during rain. Bivalves are generally eaten
raw or after light cooking that does not inactivate viruses.
Prevention of contamination by food handlers relies on the adoption of appropriate
work practices. Food handlers must not work while suffering from intestinal illness.
Food handlers must practise good personal hygiene and should use food-handling
Page 155 of 189
techniques that prevent the contact between the hands and foods that will not
receive a virucidal treatment.
Control of shellfish-borne viral illness is difficult. The main measure is ensuring that
shellfish growing areas are sufficiently remote from sources of pollution with human
waste to be considered safe. This has reduced the incidence of shellfish-borne illness
but failed to eliminate the transmission of viruses (ICMSF, 1996).
Survival of noroviruses
Based on infectivity in human dose response research studies norovirus is stable and
resistant to heat, acid and solvents. The virus retained infectivity after incubation at
60°C for 30 min. Pasteurisation is not sufficient to eliminate viruses. Resistance is
reported to be greater in foods and shellfish. Steaming of oysters might not
inactivate norovirus (Greening et al, 2003).
Under refrigeration and freezing conditions the virus remains intact (and presumably
viable) for several months, possibly years. Freezing generally does not inactivate
viruses. Norovirus resists gastric acids at pH 3–4. The virus retained infectivity after
exposure to pH 2.7 for 3 hours at room temperature. It is believed to be sensitive to
pH >9.0 but this is unproven.
Norovirus is resistant to drying. Infectious norovirus were detected on environmental
surfaces, including carpets, for up to 12 days after outbreaks in institutions.
Survival of Hepatitis A
Hepatitis A is caused by a nonenveloped RNA picornavirus that infects only primates.
Lack of a lipid envelope confers resistance to bile lysis. The virus is hardy, surviving
on human hands and fomites and requiring temperatures higher than 85°C for
inactivation. Hepatitis A virus survives for extended periods in seawater, fresh water,
wastewater, and soil. The virus is resistant to freezing, detergents, and acids, but it
is inactivated by formalin and chlorine (Brundage & Fitzpatrick, 2006).
Scombroid poisoning
Scombroid poisoning or ‘histamine fish poisoning’ is the most common form of
toxicity caused by the ingestion of fish (Hahn & Capra, 2003). It is caused by the
ingestion of food that contains high levels of histamine and possibly other vasoactive
amines and compounds. Histamine and other amines are formed by the growth of
certain bacteria and the subsequent action of their decarboxylase enzymes on
histadine and other amino acids (FDA, 1992).
Fishery products that have been implicated in Scombroid poisoning include tuna,
mackerel and other fish with dark flesh. However, any food that contains the
appropriate amino acids and is subject to certain bacterial contamination and growth
may lead to scombroid poisoning. For example, Swiss cheese has been implicated
with intoxication.
Neither cooking, canning nor freezing reduces the toxic effect. Common sensory
examination by the consumer cannot ensure the absence or presence of the toxin
(FDA, 1992). Prevention of scombroid poisoning in fish can be achieved by
appropriate post harvest practice. Handle fish hygienically to reduce bacterial
contamination and ice fish to control decomposition.
Page 156 of 189
Ciguatera
Ciguatera poisoning is caused by the consumption of toxic fish from tropical and subtropical marine environments. Ciguatera has a circumtropical distribution, usually in
close association with coral reefs. It is caused by ingestion of small quantities of a
group of closely related, very powerful toxins that occur in the tissues of offending
fish. The toxins are bioaccumulated by fish through dietary exposure prior to
capture.
Toxin and toxin precursors are produced by a dinoflagellate alga named
Gambierdiscus toxicus. Ciguatoxins enter the human food chain by grazing fish and
then move through the various trophic levels. In Australia ciguatera poisoning in
humans usually occurs after consumption of high level carnivorous fish such as
Spanish mackerel and coral trout.
After ingestion the illness often follows a reasonably predictable pattern. Initial
symptoms usually occur about 6 hours after ingestion and include vomiting,
diarrhoea and abdominal cramps. Neurological symptoms usually begin to appear
12–18 hours after consumption of toxic fish. Symptoms can include tingling of the
lips and extremities, bone pain, muscle pain, dental pain, convulsions, muscular
paralysis, vertigo, severe headache, short term memory loss, temperature
perceptions reversals, sweating and itching.
The neurological symptoms are prominent and account for the major discomfort of
most victims. In some cases symptoms are evident for months or years (Hahn &
Capra, 2003).
Shellfish poisoning
Microscopic unicellular algae form an important component of the plankton diet of
shellfish such as oysters, mussels and scallops. Some species of dinoflagellates and
diatoms produce potent neurological toxins which can find their way though shellfish
to humans. When humans eat seafood contaminated by these microalgae, they may
suffer gastrointestinal and neurological illnesses.
These include paralytic shellfish poisoning (PSP) which in extreme cases can lead to
death through respiratory paralysis diarrhoetic shellfish poisoning (DSP) which
causes severe gastrointestinal problems and may promote stomach cancers and
amnesic shellfish poisoning (ASP) which can lead to permanent brain damage
including short-term memory loss (FDA, 1992).
Poisonous seafood neither looks or tastes different from uncontaminated seafood.
Cooking and other treatments do not destroy the toxins. If precautions are not taken
with shellfish harvest then public health problems can be considerable. Control
measures include routine monitoring of shellfish harvest areas for levels of toxic
algae and testing shellfish for toxin presence (Hallegraeff, 2003).
Mycotoxins / Aflatoxins
Toxic fungal metabolites, mycotoxins, have been responsible for a number of major
epidemics in man and animals during recent historical times. Historically, the most
important epidemics have been ergotism, which have killed hundreds of thousands of
people in the last millennium; alimentary toxic aleukia, which was responsible for the
death of at least 100,000 Russian people between 1942 and 1948;
stachybotryotoxicosis, which killed tens of thousands of horses in the USSR in the
1930s; and aflatoxicosis, which came to attention when it killed 100,00 young
turkeys in the United Kingdom in 1960 and has caused death and illness in many
other animals, including man (Hocking & Pitt, 2003).
Page 157 of 189
Table 60 – Important Aspergillus , Fusarium and P enicillium species and their
mycotoxins
Toxigenic species
Mycotoxins
Aspergillus flavus
Aflatoxins
B1, B2
Aspergillus parasiticus
Aflatoxins
B1, B2, G1,
G2
Aflatoxin M1
Hydroxylated metabolites
of aflatoxin B
Affected
commodities
Maize, peanuts,
cottonseed, oilseed,
tree nuts, spices
Maize, peanuts,
cottonseed, oilseed,
tree nuts
Milk
Toxic effects
Maize
Nuts, barley,
processed meats,
and many others
Maize, wheat
Carcinogenic
Kidney damage,
teratogenic,
immunosuppressive
Gastrointestinal symptoms
Deoxynivale
nol
Maize, wheat
Gastrointestinal symptoms
Patulin
Apple, pears
Kidney damage,
chromosomal aberration
Fusarium verticillioides
Aspergillus ochraceus,
Penicillium verrucosum
Fumonisin B1
Ochratoxin A
Fusarium graminearum,
Fusarium culmorum,
Fusarium crookwellense
Fusarium graminearum,
Fusarium culmorum,
Fusarium crookwellense
Penicillium expansum
Zearalenone
Acute liver damage,
carcinogenic, teratogenic,
immunosuppressive
Acute liver damage,
carcinogenic, teratogenic,
immunosuppressive
Carcinogenic
adapted from Hocking & Pitt (2003)
Aflatoxicosis is poisoning that results from ingestion of aflatoxins in contaminated
food or feed. Aflatoxins are toxic compounds produced by certain strains of the fungi
Aspergillus flavus and Aspergillus parasiticus. Under favourable conditions of
temperature and humidity, these fungi grow on certain foods and feeds, resulting in
the production of aflatoxins. The most pronounced contamination has been
encountered in tree nuts, peanuts and other oilseeds, including corn and cottonseed.
The major aflatoxins of concern are designated B1, B2, G1 and G2. Aflatoxin B1 is
usually prominent and is the most toxic. Aflatoxin M is a major metabolic product of
aflatoxin B1 in animals and is usually secreted in the milk and urine of dairy cattle.
Aflatoxins produce acute necrosis, cirrhosis and carcinoma of the liver in a number of
animal species. In well-developed countries contamination rarely occurs in foods at
levels that cause acute aflatoxicosis in humans. Studies on human toxicity from
ingestion of aflatoxins have focussed on their carcinogenic potential (FDA, 1992).
While it will never be possible to eliminate mycotoxins completely from the food
supply, better cropping, harvesting, storage and processing techniques can minimise
the opportunities for fungi to produce toxic metabolites in food (Hocking & Pitt,
2003).
Gempylotoxin
Purgative properties are reported for fish of the marketing groups escolar
(Lepidocybium flavobrunneum, Ruvettus pretiosus) and rudderfish (Centrolophus
niger and Tubia species). Escolar are commonly sold in the domestic market
mislabelled as 'rudderfish' or 'butterfish'. Studies have found that both escolar and
rudderfish have higher oil composition than most seafood, but it is the high wax
ester content in escolar oil that explains the purgative property. In humans,
indigestible wax esters accumulate in the rectum causing oily diarrhoea (Yohannes et
al, 2002).
Page 158 of 189
References – Appendix 1
AIFST (2003). Hocking, A.D. (Ed.). Foodborne Microorganisms of Public Health Significance.
Australian Institute of Food Science and Technology, Waterloo.
−
Barton, M.D. & Robins-Brown, R.M. (2003). Yersinia enterocolitica. (pp. 577-596).
−
Bates, J.R. & Bodnaruk, P.W. (2003). Clostridium perfringens. (pp. 479-504).
−
Desmarchelier, P.M. (2003). Pathogenic vibrio. (pp. 333-358).
−
Desmarchelier, P.M. & Fegan, N. (2003). Enteropathogenic Escherichia coli. (pp. 267310).
−
Goldsmid, J.M., Speare, R. & Bettiol, S. (2003). The parasitology of foods. (pp. 703-722).
−
Hahn, S. & Capra, M.F. (2003). Fishborne illnesses: Scombroid and ciguatera poisoning.
(pp. 689-702).
−
Hallegraeff, G.M. (2003). Algal toxins in Australian shellfish. (pp. 675-688).
−
Hocking, A.D. & Pitt, J.I. (2003). Mycotoxigenic fungi. (pp. 641-674).
−
Jay, S., Davos, D., Dundas, M., Frankish, E., & Lightfoot, D. (2003). Salmonella (pp. 207266).
−
Jenson, I. & Moir, C.J. (2003). Bacillus cereus and other Bacillus species. (pp. 445–478).
−
Sutherland, P.S., Miles, D.W. & Laboyrie, D.S. (2003). Listeria monocytogenes. (pp. 381–
443).
−
Szabo, E.A. & Gibson, A.M. (2003). Clostridium botulinum. (pp. 479-504).
−
Wallace, R.B. (2003). Campylobacter. (pp. 311-331).
Balakrish Nair, G. et al. (2007). Global Dissemination of Vibrio parahaemolyticus Serotype
O3:K6 and its Serovariants. Clinical Microbiology Reviews, Jan 2007, 39-48. Retrieved 1
September 2008, from http://cmr.asm.org/cgi/content/abstract/20/1/39
Bell, C. & Kyriakides, A. (2002). Salmonella, a practical approach to the organism and its
control in foods. Blackwell Science.
Bowen, A.B. and Braden, C.R. (2006). Invasive Enterobacter sakazakii disease in infants.
Emerging Infectious Diseases 12, August 2006 1185-1189. Retrieved from
http://wwwnc.cdc.gov/eid/article/12/8/05-1509_article.htm
Brundage, S. & Fitzpatrick, A. (2006). Hepatitis A. American Family Physician 73 (12) (web
version). Retrieved 19 December 2008, from
http://www.aafp.org/afp/AFPprinter/20060615/2162.pdf
Davos, D. (2007). Australian Salmonella Reference Centre 2007 Annual Report, Institute of
Medical and Veterinary Science.
EC SCF [European Commission, Scientific Committee on Food] (2002). Risk profile on the
microbiological contamination of fruits and vegetable eaten raw, 29 April 2002. European
Commission Health & Consumer Protection Directorate-General, Scientific Committee on
Food. Retrieved 8 December 2008, from http://ec.europa.eu/food/fs/sc/scf/out125_en.pdf
FDA (1992). The “Bad Bug Book” - Foodborne Pathogenic Microorganisms and Natural Toxins
Handbook US Food and Drug Administration, Center for Food Safety and Nutrition. Originally
published 1992, with periodic updates. Retrieved 25 August 2008 from
http://www.cfsan.fda.gov/~mow/intro.html
Friedman C. R. et al. (2004). Risk Factors for Sporadic Campylobacter Infection in the United
States: A Case-Control Study in FoodNet Sites. Clinical Infectious Diseases 38(3), S285-96.
Retrieved 25 August 2008, from http://origin.cdc.gov/enterics/publications/70_friedmanc.pdf
Page 159 of 189
FSAI [Food Safety Authority of Ireland] (2007). Guidance Note 22: Information Relevant to
the Development of Guidance Material for the Safe Feeding of Reconstituted Powdered Infant
Formula. Retrieved 12 September 2008, from
http://www.fsai.ie/publications/guidance_notes/gn22.pdf
Greening, G., et al (2003) Risk Profile: Norwalk-like Virus in Mollusca (Raw). Institute of
Environmental Science and research Ltd, Christchurch, NZ.
Microorganisms in Foods 5: Microbiological specifications of food pathogens. Roberts, T.A.,
Baird-Parker, A.C. & Tompkin, R.B. (Eds.). Blackie Academic & Professional.
Lake, R. Hudson, A., Cressey, P. & Gilbert, S. (2005). Risk Profile: Listeria monocytogenes in
soft cheeses. Institute of Environmental Science and Research Limited report prepared for the
Peck, M.W., Goodburne, K.E., Betts, R.P. & Stringer, S.C. (2008). Assessment of the potential
for growth and neurotoxin formation by non-proteolytic Clostridium botulinum in short shelflife commercial foods designed to be stored chilled. Trends in Food Science & Technology
19(4), 207-216.
Yohannes, K. et al. (2002). An outbreak of gastrointestinal illness associated with the
consumption of escolar fish. Communicable Diseases Intelligence, Volume 26(3). Retrieved 11
September 2008, from http://www6.health.gov.au/internet/main/publishing.nsf/Content/cdapubs-cdi-2002-cdi2603-htm-cdi2603l.htm
Page 160 of 189
Appendix 2: Australian food recalls
(2004–2008)
Table 61 – Recalls of dairy products between 2004 and 2008
Product
Reason for recall
1. Ice-cream cake
2. Custard
Escherichia coli
3. Haloumi
4.
5.
6.
7.
Yoghurt
Custard
Cream
Milk, UHT,
flavoured
(variety)
8. Cheese, soft
9. Cheese, soft
10. Bocconcini, soft
11. Cheese, hard
12. Cream
13. Cream
14. Goats cheese
15.
16.
17.
18.
Milk
Infant formula
Ricotta
Cheese, hard +
ingredients
19. Dairy dessert
20. Cheese, hard +
ingredients
21. Mozzarella,
shredded
22. Milk, goats,
frozen
unpasteurised,
23. Cheese, hard
24. Feta
25. Ice-cream +
ingredients
qq
Was the recall
instigated due to
illness?
Not reported
Not reported
Distribution
Year
WA
National qq
2004
2004
Not reported
VIC
2004
Not reported
Not reported
Not reported
n/a
NSW
National
WA
National
2004
2004
2004
2005
No
National
2005
No
No
WA
NSW, ACT
2005
2005
No
National
2006
No
No
No
NSW
NSW
National
2006
2006
2006
No
No
No
No
NSW, ACT
National
QLD
National
2006
2007
2007
2007
Listeria
monocytogenes
Escherichia coli
No
NSW
2007
No
NSW
2007
Listeria
monocytogenes
Salmonella Zanzibar
No
VIC
2008
No
QLD
2008
No
National
2008
No
National
2008
No
NSW
2008
Possibility of spoilage
before expiry date
Coagulase positive
staphylococcus
Escherichia coli
Microbial spoilage
Escherichia coli
may spoil before
expiry date.
Listeria
monocytogenes
Escherichia coli
Listeria
monocytogenes
Listeria
monocytogenes
Escherichia coli
Escherichia coli
Listeria
monocytogenes
Escherichia coli
mould
mould (Salmonella)
Salmonella
Listeria
monocytogenes
Listeria
monocytogenes
Listeria
monocytogenes
National includes distribution to three or more states and territories
Page 161 of 189
Table 62 – Recalls of meat products between 2004 and 2008
Product
Reason for recall
1.
2.
3.
4.
5.
6.
7.
8.
Chicken, BBQ,
shaved
Ham, sliced
Pork, pickled
Beef, roast,
sliced
Ham, sliced
Brawn
Frankfurts
Salami
Distribution
Year
Was the recall
instigated due
to illness?
Not reported
WA
2004
Not reported
Not reported
Not reported
NSW
NSW
NSW
2004
2004
2004
Not
Not
Not
Not
reported
reported
reported
reported
NSW
NSW
National
National
2004
2004
2004
2004
Insufficient salt added
during processing that
may result in microbial
growth
9. Meat, roast
10. Chicken, breast,
sliced
11. Pork pies
12. Devon
Not reported
No
National
VIC
2004
2005
Escherichia coli
No
No
WA
National
2005
2005
13. Smallgoods
(variety), sliced
14. Smallgoods
(variety), sliced
15. Silverside
16. Chicken, whole,
smoked
17. Smallgoods
18. Lamb, sliced
19. Cacciatore
20. Chicken breast,
shaved
21. Prosciutto
Ham, slices &
whole legs
22. Smallgoods
23. Silverside
24. Beef, cooked,
sliced
25. Ham
Silverside, sliced
26. Pastrami
27. Cabanossi
28. Chicken breast,
smoked
29. Ham, sliced
30. Bacon
31. Ham
32. Beef, cooked,
sliced Pastrami,
sliced
33. Chicken breast,
sliced
No
QLD
2005
No
National
2005
No
No
VIC, NSW
NSW, ACT
2006
2006
Salmonella
Not reported
No
No
No
National
National
NSW
National
2006
2006
2007
2007
No
NSW
2007
Salmonella
No
No
No
National
National
SA, NT
2007
2007
2007
No
QLD
2007
No
No
No
National
National
National
2007
2008
2008
Listeria
Listeria
Listeria
Listeria
monocytogenes
monocytogenes
monocytogenes
monocytogenes
No
No
No
No
National
QLD
National
National
2008
2008
2008
2008
No
National
2008
Some product not
thoroughly cooked.
Page 162 of 189
Table 63 – Recalls of plant products between 2004 and 2008
Product
Reason for recall
1. Peppercorns
2. Mushrooms, in
brine
Salmonella
3. Parsley, fresh
4. Alfalfa
Listeria
monocytogenes,
Salmonella
Salmonella
5. Alfalfa
6. Sprouts
7. Orange juice
Escherichia coli
Salmonella
Not commercially
sterile – suspected
under processing
Oranienburg
Salmonella, Listeria
Was the recall
instigated due to
illness?
Not reported
No
Distribution
Year
National
National
2004
2005
No
National
2006
No
WA
2006
No
No
No
VIC, TAS
National
NSW, VIC
2006
2007
2007
Table 64 – Recalls of seafood products between 2004 and 2008
Product
1.
2.
3.
4.
5.
6.
7.
Prawns, cooked
& peeled
Mackerel, in oil
Salmon,
smoked, sliced
Prawns, frozen,
cooked & peeled
Clams, frozen
Tuna, steaks
Tuna, canned
Reason for recall
Was the recall
instigated due to
illness?
not reported
Distribution
Year
National
2004
Histamine
not reported
Not reported
National
NSW
2004
2004
Microbial
contamination
Potential
No
SA, QLD
2005
No
National
2005
Yes
No
SA
National
2008
2008
Salmonella Infantis
Listeria
monocytogenes
Salmonella
contamination
Histamine
Potential
pathogenic
contamination
Page 163 of 189
Appendix 3: Australian foodborne illness outbreaks
(1995–2008)
The tables on the following pages list foodborne illness outbreaks affecting two or
more people from 1995 to 2008 and attributed to foods that are regulated by the
food safety schemes contained in the Food Regulation 2004, or where those foods
were included as an ingredient in the food implicated in the outbreak.
These tables use the epidemiological data from the following sources:
•
Food Science Australia & Minter Ellison Consulting (2002). National Risk Validation
Project. Final Report.
•
OzFoodNet Working Group (2002). Enhancing foodborne disease surveillance across
Australia in 2001: the OzFoodNet Working Group. Communicable Diseases
Intelligence, 26(3), 375–406.
•
OzFoodNet Working Group (2003). Foodborne disease in Australia: incidence,
notifications and outbreaks. Annual report of the OzFoodNet network, 2002.
Communicable Diseases Intelligence, 27(2), 209–243.
•
OzFoodNet Working Group (2004). Foodborne disease investigation across Australia:
Annual report of the OzFoodNet network, 2003. Communicable Diseases Intelligence,
28(3), 359–389.
•
OzFoodNet Working Group (2005). Reported foodborne illness and gastroenteritis in
Australia: Annual report of the OzFoodNet network, 2004. Communicable Diseases
•
OzFoodNet Working Group (2006). Burden and causes of foodborne disease in
Australia: Annual report of the OzFoodNet network, 2005. Communicable Diseases
•
OzFoodNet Working Group (2007). Monitoring the Incidence and Causes of Diseases
Potentially Transmitted by Food In Australia: Annual Report of the OzFoodNet
network, 2006 Communicable Diseases Intelligence, 31(4), 345–365.
Key for contributing factors
Temperature misuse
T1
T2
T3
T4
T5
Inadequate handling
C1
C2
Inadequate environment E1
E2
Raw material
R1
R2
R3
Process
P
a
(CF)
Improper heating
Improper reheat
Inadequate storage
Preparation far in advance
Inadequate thawing
Food handler contamination
Cross contamination
Insufficient hygiene
Inadequate facilities
Contaminated raw ingredient
Infected animals
Food from unsafe source
Inadequate process
Assumption made on the basis
of information available, eg implicated microorganism,
normal mode of transmission
Page 164 of 189
Table 65 – Foodborne illness outbreaks attributed to milk, dairy products and dairy products used as an ingredient
State
Year
Food vehicle
Agent
SA
SA
WA
SA
VIC
SA
VIC
ACT
QLD
VIC
VIC
WA
NSW
VIC
VIC
NSW
QLD
QLD
SA
VIC
SA
QLD
1997
1998
1998
1999
1999
2000
2000
2001
2001
2001
2001
2001
2002
2002
2002
2003
2003
2003
2003
2003
2004
2005
Cheese sauce
Gelato
Unpasteurised milk 44
Unpasteurised milk
Continental custard cake
Unpasteurised milk
Unpasteurised milk
Cheese sticks
Unpasteurised pets milk (cow)
Unpasteurised milk
Unpasteurised milk (suspected)
Cranachan (dessert)
Cream filled cake
Cream filled cakes/pastries
Cheesecake (suspected)
Apple strudel
Cheese
Trifle
Unpasteurised milk
Unpasteurised milk/animal contact
Creamed cakes
Custard filled dumplings
C. perfringens
S. Oranienburg
Campylobacter
S. Typhimurium 44
S. Typhimurium 9
Campylobacter
Campylobacter
SA
NSW
VIC
SA
2006
2007
2007
2008
Sweet potato and feta cheese salad
Fruit, meringue and custard tart
Fetta cheese (suspected)
Milk (suspected)
S. Typhimurium 9
Unknown
Unknown
Unknown
44
unknown
Cryptosporidiosis
Unknown
Campylobacter
Contributing
factors (CF)
C2
C2
R3
R3
T3a
R3
R3
T3
R3
Unknown
S. Typhimurium 135
S. Typhimurium U290
Norovirus
Norovirus
Sorbic acid
Norovirus
Campylobacter
Campylobacter
S. Typhimurium 108
S. aureus
R3
Number
affected
27
102
9
12
54
12
25
2
8
12
12
50
29
10
25
67
23
31
14
13
13
2
Hospitalised
(deaths)
6
9
10
5
0
3
0
0
1
0
1
0
0
0
5
-
Setting prepared
Commercial caterer
Manufacturer
Camp
Farm
Bakery
Retail dairy
Camp
Restaurant
Community
Camp
Camp
Function
Bakery
Bakery
Commercial caterer
Restaurant
Childcare
Restaurant
Camp
Camp/excursion
Bakery
Grocery
store/delicatessen
Restaurant
Unknown
Restaurant
Camp
Unpasteurised cows milk is not currently regulated under the dairy food safety scheme or the Food Standards Code, however FSANZ is reviewing the regulatory requirements relating to
unpasteurised milk as part of Proposal P1007 - Primary Production & Processing Requirements For Raw Milk Products
Page 165 of 189
Table 66 – Foodborne illness outbreaks attributed to meat, meat products and meat products used as an ingredient
State
Year
Food vehicle
Agent
ACT
NSW
NSW
NSW
NSW, ACT,
QLD, VIC
SA
ACT
1995
1995
1995
1995
1995
Roast chicken
Deboned roast pork
Sandwiches
BBQ chicken
Meat or chicken
S. Bredeney
S. Typhimurium pt 9
1995
1995
E. coli O:111
S. Bredeney
QLD
NSW
NSW
VIC
NSW
1996
1996
1996
1996
1996
NSW
1997
NSW
NSW
NSW
SA
VIC
VIC
VIC, SA
WA
NSW
1997
1997
1997
1997
1997
1997
1997
1997
1998
Mettwurst (uncooked)
Cold chicken, salad, prawns,
custard
Anglaise sauce
Ham sandwiches (suspected)
Chicken soup
Beef & pork cooked on spit
Beef, chinese cabbage &
sprouts
Chicken or thai-style beef
salad
Cold chicken pieces
Meat loaf & gravy
Turkey/pork
Bread rolls with meat filling
Beef/lamb curry with rice
Ham & corned beef
Sliced corned beef / ham
Roast lamb
Ham & potato bake
SA
SA
1998
1998
Ham
Spatchcock
S. sonnei biotype g
S. Typhimurium rdnc
SA
SA
1998
1998
Chicken nuggets
Steak roll
S. Typhimurium 12
Suspected viral
Unknown
S. Bredeney
S. Heidelberg pt 16
Norwalk-like virus
Suspected viral
C. perfringens
S. Typhimurium 135
C. perfringens
S. Typhimurium pt 9
Unknown
S. Typhimurium 135
S. Typhimurium 135
C. perfringens
S. Anatum
S. Muenchen
C. perfringens
L. monocytogenes
(non-invasive)
ao45
Unknown
Contributing
factors (CF)
T1a
T1 C2
T3 C1
T3
C2
Number
affected
3
22
17
19
157
Hospitalised
(deaths)
E1 P
U
173
14
unknown (1)
R1 R3
C2a
C1
T3
C1 C2 E1
>500
20
67
33
17
T3 C2
171
T3 C2 E2
U
T1 T3
T1a T3a C2a E2a
T3a
C2a Pa
T3 C2
T3a
T1 T3
78
8
85
71
9
25
32
12
32
C1
T1 T2
13
38
T1
U
18
200
1
23
4
5
Setting prepared
Takeaway
Camp
Commercial caterer
Private residence
Takeaway
Manufacturer
Commercial caterer
Commercial
Commercial
Commercial
Commercial
Restaurant
caterer
caterer
caterer
caterer
Commercial caterer
3
2
unknown (2)
Function
Institution
Institution
Manufacturer
Commercial caterer
Manufacturer
Manufacturer
Commercial caterer
Commercial caterer
Commercial caterer
Commercial caterer
Private residence
Takeaway
Page 166 of 189
State
Year
Food vehicle
Agent
Suspected viral
S. Typhimurium 64
S. Typhimurium 64
Unknown
S. Typhimurium
TAS
VIC
VIC
NSW
NSW
QLD
QLD
QLD
QLD
VIC
VIC
VIC
VIC
1998
1998
1998
1999
1999
1999
1999
1999
1999
1999
1999
1999
1999
VIC
VIC
ACT
ACT
ACT
NSW
1999
1999
2000
2000
2000
2000
NSW
NSW
NSW
NSW
NT
QLD
2000
2000
2000
2000
2000
2000
Chicken
Chicken meal
Cooked chicken
Salami (suspected)
Chicken kebab
Spit roast pork
Roast lamb
Meat pie
Curried chicken
Chicken vol au vents
Pancake with meat filling
Chicken briyani
Stir-fry chicken & vegetable
(or sweet and sour pork)
Chicken vietnamese dish
Chicken/beef satay, beef dish
Chicken breast
Lamb curry
Venison stew
Range of foods especially
sliced smallgoods and
antipasto
Thai beef salad
Beef enchiladas/nachos
Roast beef & roast pork
Meat pie & gravy
Chicken-a-la-king
Burger (suspected)
QLD
QLD
QLD
QLD
VIC
2000
2000
2000
2000
2000
Steak salad & chip meal
Chicken meal
Lemon chicken
Chicken
Frankfurters
C. perfringens
Viral
C. perfringens
C. perfringens
C. perfringens
S. Hessarek
S. aureus
C. perfringens
Unknown
S. Virchow 34
Unknown
C. perfringens
Unknown
Norwalk-like virus
Salmonella spp
Unknown
C. perfringens
Unknown
C. perfringens
Unknown
Unknown
S. aureus
Suspected viral
Unknown
S. Typhimurium 9
Contributing
factors (CF)
C1a
T1
T1a T3a C2a
E1
T3
T1 T3
C1
T3
T3
T3
T1 T3 C2
T3a
T3
Number
affected
15
32
46
92
4
29
74
>2
3
>34
>11
35
16
T3
T1 C2
T3
T3
T3
C1
>14
32
3
14
2
35
T3
C1
T3 E1
U
T3
U
21
3
5
3
56
2
C2
T3 C2
C1a
U
T1
5
3
2
4
5
Hospitalised
(deaths)
Setting prepared
Commercial caterer
Restaurant
Takeaway
Function
Takeaway
Commercial caterer
Commercial caterer
Manufacturer
Takeaway
Commercial caterer
Commercial caterer
Private residence
Private residence
1
1
1
Restaurant
Wholesaler
Restaurant
Restaurant
Restaurant
Commercial caterer
Restaurant
Restaurant
Restaurant
Bakery
Commercial caterer
National franchised fast
food
Restaurant
Takeaway
Takeaway
Takeaway
Private residence
Page 167 of 189
State
Year
Food vehicle
Agent
S. Typhimurium 170
S. Virchow pt 34
Campylobacter
S. Typhimurium pt64
VIC
VIC
2000
2000
Sucuk
Chicken kebabs
ACT
ACT
ACT
ACT
ACT
ACT
NSW
NSW
NSW
NSW
NSW
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
NSW
NSW
NSW, VIC
QLD
QLD
QLD
QLD
QLD
QLD
QLD
QLD
SA
SA
SA
VIC
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
2001
VIC
2001
Spit roast meal (suspected)
Spit roast
Chicken burger
Prawn stuffed chicken breast
Honey chicken (suspected)
Roast beef with gravy
Chicken pizza
Takeaway chicken
(suspected)
Chicken kebab (suspected)
BBQ chicken (suspected)
Chicken kebab
Cajun chicken
Chicken salad in pita bread
Chicken
Duck liver
Beef curry
Beef curry
Chicken kebabs
Chicken kebabs
Chicken
Chicken
Homemade italian sausages
Soup or roast beef
(suspected)
Lamb's fry
Suspected
Suspected
Suspected
Suspected
Unknown
Unknown
Unknown
Unknown
Contributing
factors (CF)
T1 R3 P
T1
toxin
toxin
toxin
toxin
C. perfringens
S. Typhimurium 126
U
U
C2
T3
Unknown
Unknown
Unknown
S. Virchow pt 36 var 1
B. cereus
S. Bovismorbificans 32
S. Virchow pt 8
Campylobacter
C. perfringens
C. perfringens
C. jejuni
C. jejuni
S. Typhimurium 126
Salmonella serovars
S. Typhimurium 135a
Suspected toxin
S. Typhimurium 99
T1 C2
T3a
T3
T1
R1
Number
affected
8
3
Hospitalised
(deaths)
Private residence
Takeaway
22
110
68
31
9
3
9
10
27
2
2
0
0
0
0
2
3
38
6
36
2
2
8
15
3
3
88
50
2
269
0
0
22
Setting prepared
0
1
0
Function
Function
Function
Function
Restaurant
Takeaway
Commercial caterer
Restaurant
Restaurant
Takeaway
Takeaway
0
0
Takeaway
Takeaway
Takeaway
Commercial caterer
Community
Function
Restaurant
Restaurant
Restaurant
Takeaway
Takeaway
Community
Farm
Private residence
Function
2
Hotel
6
0
0
0
0
unknown
Page 168 of 189
State
Year
Food vehicle
Agent
C. perfringens
C. perfringens
S. Typhimurium 43
S. Typhimurium 135
S. Typhimurium 135
VIC
2001
VIC
VIC
VIC
VIC
WA
WA
2001
2001
2001
2001
2001
2001
NSW
NSW
NSW
NSW
NSW
NSW
NSW
NSW
NSW
NSW
NSW
NSW
NSW
QLD
QLD
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
Potato and bacon soup
(suspected)
BBQ chicken/meat
Eye fillet meal
Sausages (suspected)
Kebabs (suspected)
Chicken (suspected)
Undercooked turkey
(suspected)
Spit roast beef/and or pork
Chicken casserole
Chicken
Beef dish (suspected)
Beef curry
Lamb curry
Bbq chicken
Pasta (suspected)
Thai salad
Baked beans/chilli con carne
Kebabs (suspected)
Pizza
Pizza
Chicken
Pizza
SA
SA
VIC
VIC
VIC
VIC
NSW
NSW
NSW
2002
2002
2002
2002
2002
2002
2003
2003
2003
Potato and meat pie
Sliced ham
Roast chicken
Home bbq chicken
Pea and ham soup
Steak or sauce
Chicken
Chicken / eggs (suspected)
Soccerball ham
Contributing
factors (CF)
S. Virchow 34
S. Typhimurium 99
Norwalk virus
Unknown (1 positive Salmonella)
Norwalk virus
Unknown
C. perfringens
Unknown
S. Virchow
Unknown
Unknown
C. perfringens
Unknown
Unknown
S. Typhimurium 126
S. Typhimurium 9
Unknown
Unknown
Unknown
C. jejuni
S. aureus
Unknown
Unknown
Campylobacter
S. Typhimurium
Unknown
Number
affected
9
11
95
65
3
56
6
Hospitalised
(deaths)
0
Hotel
2
1
0
1
0
0
Private residence
Restaurant
Restaurant
Takeaway
Function
Restaurant
0
2
0
Commercial caterer
Commercial caterer
Fast food outlet
Restaurant
Restaurant
Restaurant
Takeaway
Private residence
Restaurant
School
Takeaway
Takeaway
Takeaway
Community
food
Private residence
Community
Private residence
Private residence
Restaurant
Restaurant
Camp/excursion
Community
Private residence
16
3
3
4
2
70
2
20
21
132
2
4
5
24
8
8
5
19
6
10
5
19
20
1
Setting prepared
Page 169 of 189
State
Year
Food vehicle
Agent
Salmonella
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. aureus
NSW
NSW
NSW
NSW
NSW
NT
2003
2003
2003
2003
2003
2003
NT
NT
NT
QLD
QLD
VIC
VIC
VIC
NSW
2003
2003
2003
2003
2003
2003
2003
2003
2004
Pork dish
Chicken
Pigeon meat
Chicken
Pigs ear salad, ducks gizzard
Rice, beef and black bean
sauce
Quail (suspected)
Pizza
Roast turkey (suspected)
Beef burgundy
Roast pork
Roast pork
Roast pork
Club sandwiches
BBQ meat pizza (suspected)
NSW
2004
Roast pork
NSW
NSW
NSW
NSW
NSW
NSW
NSW
QLD
2004
2004
2004
2004
2004
2004
2004
2004
Chicken
Cold chicken sandwiches
chicken (suspected)
Bacon and ham (suspected)
Chicken (suspected)
Takeaway chicken
Chicken
Meat pizza
QLD
VIC
ACT
ACT
NSW
NSW
2004
2004
2005
2005
2005
2005
Chicken kebab
Chicken vol au vents
Pork bruschetta & duck tart
Chicken salad & chicken pasta
Beef casserole
Lambs liver
Unknown
Unknown
S. Typhimurium
Unknown
Contributing
factors (CF)
Number
affected
4
3
61
12
20
5
Hospitalised
(deaths)
1
0
5
0
0
4
Unknown
Unknown
10
18
7
7
21
20
12
17
5
0
0
0
0
2
0
0
0
1
S. Typhimurium 170,
27
1
Salmonella
S. Typhimurium
S. Typhimurium
Rdnc
S. Typhimurium 170
Unknown
Campylobacter
Unknown
S. Typhimurium 170
Unknown
S. Typhimurium 12
C. perfringens
Campylobacter
Suspected toxin
Norovirus
Campylobacter
Unknown
S. Typhimurium 197
13
7
21
12
3
5
141
6
2
20
25
11
13
43
3
0
1
0
1
0
unknown
0
0
0
1
1
0
13
Setting prepared
Restaurant
Restaurant
Restaurant
Takeaway
Takeaway
Camp/excursion
Commercial caterer
Private residence
Takeaway
Restaurant
Restaurant
Commercial caterer
Commercial caterer
Commercial caterer
food
Other
Restaurant
Restaurant
Restaurant
Restaurant
Takeaway
Takeaway
Unknown
food
Takeaway
Commercial caterer
Commercial caterer
Restaurant
Commercial caterer
Private residence
Page 170 of 189
State
Year
NSW
NSW
NSW
NSW
NSW
NSW
2005
2005
2005
2005
2005
2005
QLD
2005
QLD
QLD
QLD
SA
VIC
VIC
VIC
VIC
NSW
NSW
NSW
2005
2005
2005
2005
2005
2005
2005
2005
2006
2006
2006
NSW
NSW
NSW
2006
2006
2006
NSW
NT
2006
2006
QLD
QLD
QLD
QLD
2006
2006
2006
2006
QLD
2006
Food vehicle
Agent
Chicken caesar salad burger
Lamb & beef
Chicken
Chicken
Ham pizza
Chicken, rice, coleslaw,
potatoes
Chicken kebabs
Unknown
Unknown
Unknown
Unknown
Unknown
S. Typhimurium 9
Beef rendang
Chicken and lamb guvec
Chicken meat
Marinated chicken roll
Veal rolls & red curry
Chicken vol-au-vents
Gravy & pork
Pork (suspected)
Chicken curry
Cooked chicken
Pork dish or fried ice-cream
(suspected)
Chicken pizza
Chicken schnitzel in gravy
Chicken/beef burgers with
eggs (suspected)
Roast pork
Sticky rice balls with chicken
(suspected)
Chow mien
Chicken teriyaki sushi roll
Chicken and lamb guvec
Chicken teriyaki sushi rolls
(suspected)
Lamb korma
C. perfringens
C. perfringens
S. Typhimurium 170/108
Contributing
factors (CF)
Campylobacter
Number
affected
3
5
2
2
9
4
Hospitalised
(deaths)
2
0
0
0
0
3
Setting prepared
Restaurant
Restaurant
Restaurant
Restaurant
Restaurant
Takeaway
4
0
C. perfringens
B. cereus
S. Typhimurium 170
3
14
2
9
40
29
17
20
70
14
2
0
0
1
0
0
0
1
0
0
2
Grocery
store/delicatessen
Restaurant
Restaurant
Takeaway
Restaurant
Commercial caterer
Commercial caterer
Commercial caterer
Restaurant
Commercial caterer
Commercial caterer
Restaurant
Unknown
Unknown
S. Typhimurium 170
2
3
4
0
0
2
Restaurant
Takeaway
Takeaway
C. perfringens
S. Oslo
80
2
0
0
Takeaway
Private residence
S. Singapore
2
2
13
6
1
0
0
1
Restaurant
Restaurant
Restaurant
Restaurant
6
0
Restaurant
Unknown
Unknown
Unknown
Unknown
C. perfringens
S. Typhimurium 135
C. perfringens
Page 171 of 189
State
Year
Food vehicle
Agent
Contributing
factors (CF)
Number
affected
4
5
23
4
5
15
Hospitalised
(deaths)
0
0
7
0
0
4
Setting prepared
QLD
SA
SA
SA
VIC
WA
2006
2006
2006
2006
2006
2006
Beef/lamb kebab (suspected)
Chicken dish
Ravioli
Silverside
Salami (non commercial)
Capocollo
Unknown
NSW
2007
Unknown
9
NSW
2007
S. Typhimurium 12
7
Restaurant
NSW
NSW
NSW
NSW
2007
2007
2007
2007
Unknown
Unknown
Unknown
Unknown
5
4
5
4
Restaurant
Takeaway
Takeaway
Takeaway
NSW
NT
QLD
QLD
VIC
2007
2007
2007
2007
2007
Campylobacter
S. Oslo
2
3
7
8
5
Takeaway
Commercial caterer
Private residence
Restaurant
Restaurant
VIC
VIC
NSW
2007
2007
2008
Unknown
Unknown
17
20
75
Takeaway
Commercial caterer
Commercial caterer
NSW
NSW
NSW
QLD
QLD
SA
VIC
2008
2008
2008
2008
2008
2008
2008
Chicken stir-fry / beef
massaman
Marinated chicken dish,
noodle dish, fried rice
(suspected)
Chicken schnitzel (suspected)
Fried chicken (suspected)
Hot dogs
Beef & chicken kebabs
(suspected)
Meat kebab
Roast pork (suspected)
Wurst
Duck pâté
Chicken massaman curry
(suspected)
Meat curry (suspected)
Roast chicken and/or stuffing
Chicken curry, curry pumpkin,
rice with lamb, plain rice
Chicken rissoles (suspected)
Chilli beef dish
Stir-fry beef
Chicken
Chicken liver pâté
Chicken (suspected)
Chicken and pasta salad and
ham
Takeaway
Commercial caterer
Other
Private residence
Unknown
Commercial
manufactured food
Restaurant
S. Typhimurium 135
S. Typhimurium U290
5
7
2
2
4
3
18
Commercial caterer
Restaurant
Restaurant
Restaurant
Restaurant
Private residence
Commercial caterer
Campylobacter
S. Typhimurium 108
S. Typhimurium 135
S. London
Unknown
S. Typhimurium 135a
S. Typhimurium 9
C. perfringens / B. cereus
Unknown
Campylobacter
Campylobacter
S. Typhimurium 9
S. Typhimurium 170
Page 172 of 189
State
Year
VIC
2008
VIC
VIC
2008
2008
Food vehicle
Agent
Chicken and pasta salad and
ham
Chicken curry
Roast pork
Campylobacter
Unknown
S. Johannesburg
Contributing
factors (CF)
Number
affected
4
21
14
Hospitalised
(deaths)
Setting prepared
Commercial caterer
Commercial caterer
Restaurant
Page 173 of 189
Table 67 – Foodborne illness outbreaks attributed to plant products
State
Year Food vehicle
SA
1995
NSW
1998
NSW
1998
NSW, VIC, QLD, SA 1998
SA, VIC
1999
QLD
2000
ACT
2001
QLD
2001
VIC
2001
NSW
2003
VIC
2003
VIC
2004
NSW
2005
TAS
2005
WA
2005
VIC
2006
VIC
WA
2006
2006
WA
2006
NSW
NSW
NSW
QLD
2007
2007
2007
2007
VIC
VIC
NSW
2007
2007
2008
Contributing Number Hospitalised Setting prepared
factors (CF) affected
(deaths)
Cucumber
Campylobacter
C2
78
Commercial caterer
Cold salad
Unknown
U
26
1
Commercial caterer
Pasta salad or coleslaw, tossed salad Unknown
T3 C1 E1 E2
29
Commercial caterer
Semi-dried tomatoes with garlic in oil S. Virchow 8
R1 P
85
unknown (1) Manufacturer
Orange juice, unpasteurised
S. Typhimurium 135a
E1 R1
533
Manufacturer
Vegetables & dips
Unknown
C2
3
Restaurant
Salad at BBQ (suspected)
Suspected viral
61
0
Function
Lettuce
C2 E1
36
Takeaway
Tomato and cucumber salad
Campylobacter
50
0
Function
Salad (suspected)
Unknown
24
0
Restaurant
Cucumbers (suspected)
Salmonella
6
0
Community
Gourmet rolls/red onion
S. Typhimurium 12a
28
3
Commercial caterer
Self-serve salad bar
Unknown
37
1
Institution
Salad rolls/sandwiches
S. Typhimurium 135
6
0
Bakery
Alfalfa sprouts
S. Oranienburg
125
11
Contaminated primary
produce
Alfalfa sprouts
S. Oranienburg
15
2
produce
Bean shoots (suspected)
S. Saintpaul
11
1
Restaurant
Rockmelon
S. Saintpaul
79
12
produce
Paw paw
S. Litchfield
17
4
produce
Watermelon (suspected)
Unknown
7
Private residence
Mushroom & cos lettuce (suspected) Unknown
6
Restaurant
Fresh fruit juice (suspected)
Unknown
6
Takeaway
Baby corn
S. sonnei biotype g
55
produce
Passionfruit coulis (suspected)
Unknown
37
Commercial caterer
Fruit salad
Norovirus
18
Commercial caterer
Fattouch salad
Unknown
17
Restaurant
Agent
Page 174 of 189
Table 68 – Foodborne illness outbreaks attributed fish and seafood products
State
Year
Food vehicle
NSW
1995
Chargrilled tuna
NSW
1995/1996 Prawns
QLD
1995
Coral trout
QLD
1995
Spanish mackerel steak
WA
1995
Coral trout
WA
1995
Pilchards
NSW
1996
Rock cod
NSW, QLD
1996
Oysters
NSW
1997
Prawns
NSW
1997
Coral trout
NSW
1997
Coral trout
NSW
1997
Pipis
NSW
1997
Marlin
NSW
1997
Coral trout
NSW
1997
Prawns
NSW
1997
Fish
NSW
1997
Pipis
NSW, QLD,
1997
Oysters, raw
WA
NT
1997
Coral cod
VIC
1997
Maori wrasse fish
NSW
1998
Spotted cod
NSW
1998
Cod
NSW
1998
Spotted cod
NT
1998
Barracuda
SA
1998
Scampi
VIC
1998
Thai fish cakes
VIC
1998
Fish head soup
VIC
1998
Fish head soup
VIC
1998
Fish
VIC
1998
Seafood risotto
VIC
1998
Tuna steaks
Agent
Scombroid poisoning
S. Typhimurium
Ciguatoxin
Ciguatoxin
Ciguatoxin
Scombroid poisoning
Ciguatoxin
Norwalk-like virus
Hepatitis A
Ciguatoxin
Ciguatoxin
Diarrhoetic shellfish toxin
Scombroid poisoning
Ciguatoxin
Hepatitis A
Ciguatoxin
Diarrhoetic shellfish toxin
Hepatitis A
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Unknown
Scombroid poisoning
Ciguatoxin
Ciguatoxin
B. cereus
Scombroid poisoning
Scombroid poisoning
Contributing Number Hospitalised
factors (CF) affected (deaths)
T3
4
R3
4
R1
4
R1
15
1
R1
4
T3
>6
R1
2
R3
97
T1 R3
23
R1
6
R1
10
R1
59
T3
2
R1
6
C1a R3
17
R1
8
3
R1
56
R3
467
64 (1)
R1
R1
R1
R1
R1
R1
T1 T5 R1
T3
R1
R1
T3a
T3
T3
20
18
12
3
10
7
38
9
3
5
9
3
6
4
17
4
3
6
Setting prepared
Restaurant
Restaurant
Private residence
Retail
Private residence
Restaurant
Private residence
Community
Restaurant
Community
Community
Community
Private residence
Private residence
Restaurant
Retail
Unknown
Community
Community
Restaurant
Private residence
Private residence
Private residence
Private residence
Commercial caterer
Function
Private residence
Private residence
Restaurant
Restaurant
Restaurant
Page 175 of 189
State
Year
Food vehicle
Agent
Scombroid poisoning
NSW
NSW
NT
QLD
QLD
QLD
1999
1999
1999
1999
1999
1999
Tuna
Curried prawns
Grenadier fish fillets
Mackerel
Leatherskin/queenfish
Red claw crayfish
VIC
VIC
VIC
1999
1999
1999
Spanish mackerel
Pasta with tuna and chilli sauce
Rudderfish (butterfish)
QLD
1999
NSW
QLD
QLD
QLD
QLD
QLD
QLD
QLD
QLD
VIC
ACT
NSW
NSW
2000
2000
2000
2000
2000
2000
2000
2000
2000
2000
2001
2001
2001
Scallops or trout & ham dish, mildly
cooked prawn dumplings
Black trevally
Coronation trout
Spotted mackerel
Queenfish
Black kingfish
Coral trout
Cod
Crab cakes & sweetlip
Flake
Coral trout / coral cod
Prawns
Escolar
Fish curry made using rudderfish
QLD
QLD
QLD
QLD
QLD
QLD
QLD
2001
2001
2001
2001
2001
2001
2001
Spanish mackerel steak
Spanish mackerel
Spotted mackerel
Barracuda
Coral trout
Spanish mackerel
Spotted mackerel
C. perfringens
Scombroid poisoning
Ciguatoxin
Ciguatoxin
V. cholerae non 01, non
139
Ciguatoxin
Scombroid poisoning
Wax ester (butterfish
diarrhoea)
Norwalk-like virus
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Marine toxin
Ciguatoxin
Unknown
Escolar wax esters
Scombroid poisoning &
wax ester
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
T3
4
T3 E2
39
1
T3
5
1
R1
2
R1
7
C2
10
1
R1
T3
R1
4
unknown
>14
T1a C1a
14
R1
R1
R1
R1
R1
R1
R1
R1
R1
R1
U
R1
T3 R1
unknown
9
unknown
unknown
unknown
4
3
2
2
unknown
3
20
9
R1
R1
R1
R1
R1
R1
R1
14
14
2
3
4
9
2
Setting prepared
Private residence
Restaurant
Restaurant
Private residence
Private residence
Restaurant
Private residence
Restaurant
Restaurant
Commercial caterer
2
0
7
11
11
0
3
0
0
Private residence
Private residence
Private residence
Private residence
Private residence
Private residence
Restaurant
Restaurant
Takeaway
Private residence
Restaurant
Function
Takeaway
Commercial caterer
Private residence
Private residence
Private residence
Private residence
Private residence
Private residence
Page 176 of 189
State
Year
Food vehicle
Agent
Scombroid poisoning
Scombroid poisoning
S. Mississippi
Ciguatoxin
Ciguatoxin
diarrhoea)
Unknown
Unknown
Ciguatoxin
Unknown
Unknown
Unknown
Hepatitis A
Ciguatoxin
Ciguatoxin
Ciguatoxin
Suspected wax ester
Unknown
Norovirus
Unknown
Scombroid poisoning
Hepatitis A
Norovirus
Ciguatoxin
Ciguatoxin
Ciguatoxin
Scombroid poisoning
Ciguatoxin
QLD
QLD
VIC
VIC
VIC
VIC
2001
2001
2001
2001
2001
2001
Mahi mahi
Mahi mahi
Suspect oysters
Coral trout
Coral trout
Butterfish
NSW
NSW
NSW
NSW
NSW
NSW
NSW
QLD
QLD
QLD
VIC
WA
WA
ACT
NSW
NSW
NT
QLD
QLD
QLD
QLD
QLD
QLD
QLD
QLD
QLD
QLD
2001
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2002
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
2003
Seafood sauce (suspected)
Seafood vehicle (suspected)
Spanish mackerel
Seafood (suspected)
Seafood (suspected)
Fish
Yum cha
Striped perch
Brunter bream
Spanish mackerel
Suspect rudderfish
Oyster shooters
Seafood salad
Fish
Sardines
Prawns
Japanese IQF oysters
Coral trout
Mackerel steaks
Coral trout
Tuna patties
Fish (Mooloolaba bay)
Curried prawn dish
Cod fish heads
Giant trevally fish
Barracuda
Fish head soup - red emperor
C. perfringens
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
T3
4
0
T3
4
6
0
R1
16
0
R1
17
R1
5
0
R1
R1
R1
R1
R1
T3
R1
R1
R1
R1
T3
R1
R1
R1
R1
R1
6
5
7
3
4
2
8
2
3
2
10
unknown
60
3
2
2
48
2
3
7
2
3
19
2
3
5
3
0
0
2
0
0
0
0
0
0
0
0
0
0
5
0
Setting prepared
Restaurant
Restaurant
Community
Private residence
Private residence
Restaurant
Restaurant
Fast food outlet
Private residence
Restaurant
Restaurant
Takeaway
Restaurant
Private residence
Private residence
Takeaway
Restaurant
Commercial caterer
Restaurant
Private residence
Private residence
Restaurant
Restaurant
Private residence
Private residence
Private residence
Private residence
Private residence
Private residence
Private residence
Private residence
Private residence
Private residence
Page 177 of 189
State
Year
Food vehicle
Agent
R1
4
0
T3
3
0
R1
15
0
R1
20
0
Setting prepared
T3
R1
R1
17
22
35
3
0
0
0
0
Commercial caterer
Restaurant
Restaurant
Restaurant
R1
16
12
24
0
2
1
Restaurant
Restaurant
produce
food
Private residence
Restaurant
Restaurant
produce
produce
produce
produce
Private residence
Private residence
Private residence
Private residence
Restaurant
Takeaway
Commercial caterer
QLD
QLD
QLD
QLD
2003
2003
2003
2003
Fish species unknown
Dolphin fish
Spanish mackerel
Escolar fish
VIC
VIC
VIC
VIC
2003
2003
2003
2003
Escolar fish
Escolar fish
ACT
ACT
NSW
2004
2004
2004
Calamari Seafood (suspected)
Ling fish
Oysters
Ciguatoxin
Scombroid poisoning
Ciguatoxin
diarrhoea)
Unknown
Scombroid poisoning
Norovirus
diarrhoea)
Unknown
S. Typhimurium 197
Norovirus
NSW
2004
Fish cakes
S. Typhimurium u290
3
0
NSW
NSW
NSW
NT
2004
2004
2004
2004
Chinese style minced fish balls
Fried rice, pipis
Crab
Oysters (frozen)
S. Typhimurium u290
3
7
3
5
2
6
2
0
QLD
2004
Oysters (frozen)
Norovirus
R1
4
0
QLD
2004
Spanish mackerel/trevally
Ciguatoxin
R1
5
unknown
QLD
2004
Oysters (frozen)
Norovirus
R1
2
unknown
QLD
QLD
QLD
QLD
QLD
QLD
VIC
2004
2004
2004
2004
2004
2004
2004
Golden spotted trevally fish
Fish species unknown
Trevally
Grey mackerel
Coral trout
Grey mackerel
Butter fish (rudderfish)
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Ciguatoxin
Suspected toxin
R1
R1
R1
R1
R1
R1
R1
2
2
3
4
4
4
9
2
0
0
0
1
0
0
Unknown
S. Typhimurium 135
Unknown
Private residence
Restaurant
Restaurant
Restaurant
Page 178 of 189
State
Year
Food vehicle
Agent
VIC
2004
Redfin
Unknown
NSW
NT
QLD
2005
2005
2005
Tuna steak
Vietnamese rice paper rolls
Mackerel steaks
Scombroid poisoning
S. Typhimurium rdnc
Ciguatoxin
QLD
2005
Black trevally
Ciguatoxin
QLD
2005
Yellowtail kingfish
Ciguatoxin
QLD
2005
Spanish mackerel
Ciguatoxin
QLD
2005
Black king fish
Ciguatoxin
QLD
2005
Spanish mackerel
Ciguatoxin
QLD
2005
Trevally
Ciguatoxin
QLD
2005
Barracuda
Ciguatoxin
QLD
2005
Yellowtail king fish
Ciguatoxin
QLD
QLD
QLD
TAS
TAS
VIC
2005
2005
2005
2005
2005
2005
Prawn soup
Yellow fin tuna
Seafood mornay & rice
Seafood (suspected)
Yellow fin tuna
Fijian snapper
S. Typhimurium 44
VIC
2005
Fish
Scombroid poisoning
VIC
VIC
VIC
2005
2005
2005
Seafood platter, baked fish, octopus
Tuna
Spanish mackerel seafood (suspected)
Unknown
Scombroid poisoning
Unknown
Scombroid poisoning
Unknown
Vibrio
Scombroid poisoning
Ciguatoxin
7
3
produce
T3
4
0
Private residence
4
1
Private residence
R1
4
0
produce
R1
2
0
produce
R1
2
0
produce
R1
17
2
produce
R1
5
0
produce
R1
2
0
produce
R1
2
0
produce
R1
10
0
produce
R1
8
0
produce
23
22
Private residence
T3
2
0
Restaurant
18
0
Restaurant
2
0
Private residence
T3
2
0
Restaurant
R1
5
0
produce
T3
2
0
produce
16
0
Restaurant
T3
2
0
Restaurant
11
0
Restaurant
Page 179 of 189
State
Year
Food vehicle
Agent
NSW
2006
Tuna and salmon sushi rolls
S. Typhimurium 170
NSW
NSW
NSW
NSW
NSW
NT
2006
2006
2006
2006
2006
2006
Nile perch seafood (suspected)
Oysters seafood (suspected)
White bait
Tuna steaks
Yellowtail kingfish fillets
Slate sweetlips fish
Unknown
Unknown
QLD
2006
Cod fish heads
Ciguatoxin
QLD
2006
Blue fin tuna
Scombroid poisoning
QLD
2006
Trevally
Ciguatoxin
QLD
2006
Spanish mackerel
Ciguatoxin
QLD
2006
Spanish mackerel
Ciguatoxin
QLD
2006
Black kingfish
Ciguatoxin
VIC
2006
Coral perch or coral trout
Ciguatoxin
VIC
NSW
NSW
NSW
NSW
NSW
NT
2006
2007
2007
2007
2007
2007
2007
Kingfish
Fish balls
Tuna kebab steaks
Seafood platter
Tuna steaks
Oysters
Tinned tuna
NT
2007
Reef cod
Scombroid poisoning
Unknown
Scombroid poisoning
Norovirus
Suspect scombroid
poisoning
Ciguatoxin
QLD
2007
Mackerel
Ciguatoxin
V. cholerae
Scombroid poisoning
Scombroid poisoning
Ciguatoxin
Scombroid poisoning
B. cereus
6
0
Commercial
manufactured food
4
0
Private residence
6
0
Private residence
3
2
Private residence
T3
2
1
Restaurant
T3
6
6
Restaurant
R1
14
4
produce
R1
2
0
produce
T3
2
0
produce
R1
2
0
produce
R1
4
4
produce
R1
2
0
produce
R1
4
0
produce
R1
2
0
produce
T3
2
0
Restaurant
32
Commercial caterer
T3
3
Delicatessen
4
Restaurant
T3
2
Restaurant
R1
19
Restaurant
T3
2
Commercial
manufactured food
R1
2
produce
R1
2
produce
Page 180 of 189
State
Year
Food vehicle
Agent
QLD
2007
Mackerel
Ciguatoxin
QLD
2007
Coral trout
Ciguatoxin
QLD
2007
Mackerel
Ciguatoxin
QLD
2007
Coral trout
Ciguatoxin
QLD
2007
Coral trout
Ciguatoxin
QLD
2007
Spanish mackerel
Ciguatoxin
QLD
QLD
TAS
2007
2007
2007
Tuna
Tuna kebabs
Oysters (suspected)
Scombroid poisoning
Scombroid poisoning
Unknown
VIC
VIC
NSW
NSW
QLD
2007
2007
2008
2008
2008
Tuna
Mahi mahi
Marinated mussels (suspected)
Rice or salt & pepper prawn
Black kingfish
Scombroid poisoning
Scombroid poisoning
Unknown
Unknown
Ciguatoxin
QLD
2008
Yellowtail kingsfish
Ciguatoxin
R1
6
produce
R1
3
produce
R1
2
produce
R1
5
produce
R1
2
produce
R1
2
produce
T3
2
Private residence
T3
4
Private residence
19
produce
T3
2
Restaurant
T3
2
Restaurant
7
Restaurant
7
Restaurant
R1
6
produce
R1
2
Private residence
Page 181 of 189
Table 69 – Foodborne illness outbreaks attributed to foods served to vulnerable persons
State
Year
Food vehicle
Agent
Contributing
Number
Hospitalised
factors (CF)
affected
(deaths)
T3 C2
39
Setting prepared
NSW
1995
Unknown
Suspect S. Infantis
NSW
1995
Unknown
Unknown
U
64
NSW
1996
Eggs flip
R3
13
QLD
1996
Sandwiches
U
52
TAS
1996
Chicken with gravy
T3
32
VIC
1996
Unknown
U
2
Childcare
NSW
1996
Sandwiches & meat salad
U
5
Hospital
SA
1996
Chicken (cooked)
Salmonella serovars
S. Typhimurium
C. perfringens
E. coli O157
L. monocytogenes
L. monocytogenes o1
L. monocytogenes
C2
5
unknown (1)
Hospital
C2 R1
9
unknown (6)
Aged-care facility &
hospital
T3 T4 E1
36
T3
25
U
13
Hospital & MOW
20
Childcare
12
Aged-care facility
C1
25
Aged-care facility
8
Childcare
29
Childcare
NSW
1997–1999 Fruit salad
NSW
1997
Beef casserole
VIC
1997
Unknown
C. perfringens
C. perfringens
NSW
1998
Chicken soup
Suspect viral
NSW
1998
Unknown
Norwalk-like virus
U
S. Virchow PT 34
a
VIC
1998
Eggs
T1 R1
a
NSW
1999
Unknown
Norwalk virus
QLD
1999
Unknown
Unknown
U
R3
unknown (3)
Aged-care facility
Aged-care facility
1
unknown (1)
Aged-care facility
Hospital
Aged-care facility
Aged-care facility
unknown (1)
Aged-care facility
QLD
1999
Unknown
VIC
1999
Oranges
Salmonella serovars
S. Typhimurium 135a
QLD
2000
Egg flip
S. Heidelberg pt 1
QLD
2000
Chicken nuggets (suspected)
Norwalk virus geno 2
T1
24
Childcare
SA
2000
Unknown
Cryptosporidiosis
U
4
Childcare
SA
2000
Unknown
Rotavirus
U
12
Childcare
U
(4cx+)
SA
2000
Unknown
Rotavirus
QLD
2001
Unknown
Unknown
QLD
2001
Unknown
S. Muenchen
U
unknown
12
Childcare
6
13
Aged-care facility
Childcare
19
0
Aged-care facility
3
0
Aged-care facility
Page 182 of 189
State
Year
Food vehicle
Agent
Contributing
factors (CF)
QLD
2001
Unknown
QLD
2001
QLD
2001
SA
2001
SA
2001
VIC
2001
QLD
2002
Suspect B. cereus
QLD
2002
QLD
2002
VIC
2002
VIC
2002
VIC
2002
S. Heidelberg PT 1
S. Heidelberg PT 1
Raw eggs
S. Typhimurium 135
Rice pudding, potato pie
S. Typhimurium 135
Unknown
Campylobacter
Eggs white dish (suspected) S. Typhimurium 102
Eggs sandwiches (suspected) S. Typhimurium 135a
Eggs sandwiches (suspected S. Typhimurium 135a
Rice
S. aureus
Gravy (suspected)
C. perfringens
Gravy (suspected)
C. perfringens
NSW
2003
Chicken schnitzel
Unknown
a
a
QLD
2003
Raw eggs (suspected)
VIC
2003
Gravy (suspected)
S. Typhimurium
C. perfringens
NSW
2004
Beef curry (suspected)
Unknown
SA
2004
Unknown
SA
2004
Unknown
VIC
2004
Unknown
S. Typhimurium 126 var
Listeria
C. perfringens
VIC
2004
Unknown
Suspected toxin
VIC
2004
BBQ (suspected)
VIC
2004
VIC
Hospitalised
affected
(deaths)
Setting prepared
T3 C2 E1
19
12
6
Aged-care facility
E1 R3
12
6
Aged-care facility
17
3
Aged-care facility
18
3
Aged-care facility
49
1
Aged-care facility
Eggs (suspected)
Eggs flip
a
Number
Aged-care facility
12
Aged-care facility
12
0
Childcare
16
0
Childcare
7
Childcare
15
Aged-care facility
23
Aged-care facility
3
3
Hospital
47
16
Aged-care facility
42
DK
Aged-care facility
5
5
Hospital
13
0
Aged-care facility
2
2
Hospital
22
1
Aged-care facility
9
1
Aged-care facility
24
2
Aged-care facility
Drinking water (suspected)
Campylobacter
Campylobacter
7
0
Aged-care facility
2004
Unknown
Suspected toxin
14
unknown
Hospital
VIC
2004
Unknown
Suspected toxin
21
unknown
Hospital
QLD
2005
Braised steak and gravy
0
Aged-care facility
2005
Cold meats
3
3
Hospital
VIC
2005
Eggs (suspected)
7
2
Aged-care facility
NSW
2006
Undercooked chicken
C. perfringens
Listeria
S. Enteritidis 26 var
C. jejuni
36
SA
3
3
Aged-care facility
Page 183 of 189
State
Year
Food vehicle
Agent
Contributing
Number
Hospitalised
factors (CF)
affected
(deaths)
Setting prepared
NSW
2007
Beef sausages (suspected)
Unknown
4
Aged-care facility
NSW
2007
Tiramisu & cream, fruit salad, Unknown
strudel & custard (suspected)
6
Aged-care facility
QLD
2007
Unknown
2
Aged-care facility
SA
2007
Unknown
VIC
2007
VIC
6
Aged-care facility
Unknown
S. Kiambu
Campylobacter
S. Typhimurium 44
22
Aged-care facility
2007
Unknown
Unknown
17
Aged-care facility
VIC
2007
Unknown
6
Aged-care facility
VIC
2007
30
Aged-care facility
VIC
2007
6
Aged-care facility
VIC
2007
3
Aged-care facility
VIC
2007
4
Hospital
SA
2008
VIC
2008
Campylobacter
Several foods were suspected C. perfringens
Unknown
Campylobacter
Unknown
S. Saintpaul
Unknown
S. Typhimurium 9
Vitamised foods
S. Typhimurium 135
Unknown
C. perfringens
WA
2008
Unknown
Norovirus
38
Aged-care facility
6
Aged-care facility
42
Aged-care facility
Page 184 of 189
Table 70 – Foodborne illness outbreaks attributed to eggs, egg products and eggs used as an ingredient
State
Year
Food vehicle
Agent
Contributing
Number
Hospitalised
factors (CF)
affected
(deaths)
Setting prepared
VIC
1996
Mayonnaise
S. Typhimurium RDNC
R1
36
VIC
1997
Pork rolls
T1 T3 C2
150
8
Bakery
VIC
1997
Pork rolls
T1 T3 C2 E1
808
79
Bakery
NSW
1998
Curried eggs (suspected)
R1
11
NSW
1999
Fish & eggs sauce
R1
16
NSW
1999
Curried eggs rolls
S. Typhimurium 9
S. Typhimurium 1
S. Typhimurium 135
S. Typhimurium
Streptococcus
pyogenes Group A B-
C1
72
Institution
A015
Café
Commercial caterer
2
Commercial caterer
haemolytic
QLD
1999
Tiramisu
QLD
1999
Eggs-based dessert
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
PT 8
T3 R1
51
Restaurant
PT 8
R1
60
Restaurant
a
17
Restaurant
22
Takeaway
QLD
1999
Hollandaise sauce
ACT
2000
Curried eggs or home-made
mayonnaise
NSW
2000
2000
WA
2000
NSW
2000
SA
2001
SA
2001
S. Typhimurium
S. Mbandaka
Ice-cream dessert
S. Typhimurium
Mango mousse
S. Typhimurium
Custard tarts
S. Typhimurium
Custard tart with strawberries S. Typhimurium
PT 9
QLD
126
9
3
Takeaway
NSW
2001
17
11
Restaurant
2001
8
0
Hotel
SA
2001
11
4
Private residence
TAS
2001
9
6
1
Private residence
WA
2001
64
36
4
Restaurant
SA
2001
S. Typhimurium
S. Montevideo
Tiramisu dessert
S. Typhimurium
Duck eggs whites (suspected) S. Typhimurium
Fried ice-cream
S. Typhimurium
Mango pudding
S. Typhimurium
126
QLD
64 var
28
0
Restaurant
Fried ice-cream
135
T1
PT 9
T3 R1
C2 E1
41
T3 C2
27
Manufacturer
135
R1
53
Unknown
PT 9
C1
40
126
T3 C2 E1
9
Eggs sandwich
and a jelly glaze
Chicken, mayonnaise
Eggs
135a
2
1
Restaurant
Restaurant
Bakery
Page 185 of 189
State
SA
Year
2002
Food vehicle
Agent
S. Typhimurium 99
Deep fried ice-cream
S. Typhimurium 9
Vietnamese pork/chicken rolls S. Typhimurium 126
Eggs based dressing
S. Potsdam
Caesar salad dressing,
S. Potsdam
Custard and cream cakes
Contributing
Number
Hospitalised
factors (CF)
affected
(deaths)
22
NSW
2002
NSW
2002
NSW
2002
NSW
2002
QLD
2002
Salmon/eggs/onion/rice
patties
S. Typhimurium 135a
10
QLD
2002
Asparagus egg surprise dish
S. Hadar 22
S. Typhimurium 8
S. Typhimurium 135
S. Typhimurium 170
S. Hessarek
3
mayonnaise
Setting prepared
Bakery
8
Restaurant
32
Bakery
17
Restaurant
12
0
Restaurant
Private residence
0
Restaurant
SA
2002
Caesar salad
VIC
2002
Vietnamese pork rolls
VIC
2002
Hedgehog - possibly eggs
VIC
2002
Raw egg mayonnaise
(suspected)
VIC
2002
Caesar salad with raw egg
mayonnaise (suspected)
S. Typhimurium 135
NSW
2003
Mayonnaise
S. Typhimurium
NT
2003
Curried eggs sandwiches
Norovirus
11
0
Commercial caterer
QLD
2003
Sauces based on raw eggs
(suspected)
S. Typhimurium
18
3
Restaurant
QLD
2003
Mousse (suspected)
6
1
Private residence
VIC
2003
Pork rolls
213
22
VIC
2003
Raw eggs dishes
52
4
Restaurant
NSW
2003
Caesar salad
2
1
Restaurant
SA
2003
Cold set cheesecake
NSW
2004
Custard
NSW
2004
Tiramisu
QLD
2004
Custard fruit tarts
S. Typhimurium
S. Typhimurium
S. Typhimurium
Campylobacter
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
4
78
Restaurant
20
Bakery
6
Private residence
3
1
Restaurant
4
0
Restaurant
41
0
Restaurant
Bakery
6
1
Community
135
43
17
Institution
126
11
3
Private residence
135a
5
5
Bakery
Page 186 of 189
State
Year
Food vehicle
Agent
QLD
2004
Japanese rice balls, omelette, Mixed toxins
chicken, fish
SA
2004
SA
2004
SA
Contributing
Number
Hospitalised
factors (CF)
affected
(deaths)
Setting prepared
16
0
Restaurant
Home made ice-cream
0
Private residence
4
0
Private residence
2004
S. Typhimurium 9
S. Saintpaul
Potato bake, lemon meringue, S. Typhimurium 108
4
Boiled eggs
8
0
Private residence
VIC
2004
Sauce - raw eggs (suspected) S. Typhimurium 9
8
1
Café
VIC
2004
Eggs (suspected)
11
5
produce
ACT
2005
Hollandaise sauce
5
2
Restaurant
NSW
2005
NSW
2005
NSW
2005
NSW
2005
S. Hessarek
Raw eggs dishes (suspected) S. Typhimurium
Caesar salad dressing
S. Typhimurium
Pork rolls
S. Typhimurium
Tiramisu
S. Typhimurium
NT
2005
Vietnamese pork rolls
Unknown
QLD
2005
Eggs based filled dumplings
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
chicken patty
QLD
2005
Eggs and bacon roll
TAS
2005
Bakery products
TAS
2005
Sauces/dressing containing
raw eggs
TAS
2005
VIC
S. Typhimurium 126
9
16
-
Restaurant
44
8
2
Restaurant
9
21
1
Retail
44
7
0
Private residence
5
0
Private residence
13
7
Bakery
197
3
0
Private residence
135
107
6
Bakery
135
11
2
Restaurant
Mayonnaise & tartare sauce
S. Typhimurium 135
77
2
Restaurant
2005
Pork rolls (suspected)
Unknown
6
0
Bakery
VIC
2005
Chocolate mousse
14
5
Commercial caterer
VIC
2005
Eggs (suspected)
VIC
2005
Hollandaise sauce
ACT
2006
Free range eggs
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
ACT
2006
Free range eggs
S. Typhimurium 170
44
9
126 var 4
5
0
Private residence
9
13
5
Restaurant
44
4
1
produce
13
0
produce
Page 187 of 189
State
Year
Food vehicle
Agent
NSW
2006
Pikelets made from whole
eggs (suspected)
S. Potsdam
NSW
2006
White chocolate mousse
NSW
2006
Plain hamburger cross
contaminated with eggs
S. Typhimurium 170
S. Montevideo
NSW
2006
NSW
2006
NSW
2006
S. Typhimurium 135a
Eggs
S. Typhimurium 170
Chicken/beef hamburger cross S. Typhimurium 170
SA
2006
SA
2006
SA
2006
Beef burger with bacon &
eggs
VIC
2006
Eggs (suspected)
VIC
2006
VIC
2006
VIC
2007
NSW
NSW
Contributing
Number
Hospitalised
factors (CF)
affected
(deaths)
Setting prepared
4
0
Childcare
47
32
Institution
3
2
Takeaway
2
1
Takeaway
4
3
Takeaway
3
1
Camp/excursion
15
1
Bakery
7
0
Private residence
5
0
Restaurant
S. Typhimurium 44
Milkshake containing raw eggs S. Typhimurium 44
Hazelnut gateau cake made
S. Typhimurium 44
43
9
Community
4
4
Private residence
10
1
Private residence
Chicken foccacia/raw eggs
aioli
S. Typhimurium 44
16
2007
Eggnog
2007
Fried ice-cream
12
Restaurant
NSW
2007
Vietnamese pork & chicken
rolls
S. Typhimurium 29
S. Typhimurium 9
S. Typhimurium 9
294
Takeaway
QLD
2007
Eggs (suspected)
197
21
Community
QLD
2007
Eggs (suspected)
197
3
Restaurant
QLD
2007
Eggs (suspected)
197
12
Restaurant
QLD
2007
Eggs (suspected)
197
6
Restaurant
Eggs (suspected)
contaminated with eggs
(suspected)
S. Typhimurium 9
Homemade ice-cream and ice- S. Typhimurium 108
Eggs through a bakery
cream topping
S. Anatum
with raw eggs mousse filling
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
3
Restaurant
Private residence
Page 188 of 189
State
Year
QLD
2007
TAS
2007
VIC
2007
VIC
2007
VIC
2007
VIC
2007
VIC
2007
VIC
2007
VIC
2007
WA
Food vehicle
Agent
S. Typhimurium
Eggs (suspected)
S. Typhimurium
Pork rolls
S. Typhimurium
Milkshake includes raw eggs S. Typhimurium
Trifle - includes raw eggs
S. Typhimurium
Tiramisu - include raw eggs
S. Typhimurium
Chocolate mousse
S. Typhimurium
Caesar salad dressing includes S. Typhimurium
Eggs (suspected)
Contributing
Number
Hospitalised
factors (CF)
affected
(deaths)
Setting prepared
197
2
135a
20
Bakery
44
45
Bakery
44
4
Private residence
44
11
Private residence
44
10
Private residence
9
8
Private residence
44
15
Restaurant
Eggs used in a undercooked
food (risottini)
S. Typhimurium 44
13
Restaurant
2007
Caesar salad
75
Restaurant
QLD
2007
Cheesecake
NSW
2008
Custard cake
S. Typhimurium U307
S. Typhimurium 135a
S. Typhimurium 170
17
Private residence
VIC
2008
Continental custard cake
Unknown
21
Commercial caterer
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
S. Typhimurium
raw eggs
NSW
2008
Eggs
NSW
2008
Suspect eggs
NSW
2008
Raw eggs dressing
TAS
2008
Eggs (suspected)
TAS
2008
Eggs (suspected)
VIC
2008
Lemon dessert
VIC
2008
Eggs (suspected)/custard
dessert
VIC
2008
Suspect dessert
126/126 var 1
7
Restaurant
Bakery
41
Private residence
135
4
Private residence
126/126 var 1
3
Restaurant
135a
3
Private residence
135a
78
Restaurant
44
12
Private residence
4
Private residence
4
Restaurant
135a
S. Typhimurium 44
Page 189 of 189
NSW Food Authority
6 Avenue of the Americas
Newington NSW 2127
PO Box 6682 Silverwater NSW 1811
Phone 1300 552 406
Fax
02 9647 0026
www.foodauthority.nsw.gov.au

Food Safety Risk Assessment of NSW Food Safety Schemes

Transcription

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