Vektörle Bulaşan Hastalıklar

Vector borne diseases
Zeliha Kocak Tufan, MD, Assoc. Prof.
Infectious Diseases & Clinical
Microbiology
Vectors
• Live carrier- transmits the
infectious agent
• Insects-Athropods, ticks,
flies…
CCHF
Sand fly
fever
CDC
Chagas disease
Life-threatening condition
transmitted through triatomine bugs,
contaminated food, infected blood
transfusion. Trypanosoma cruzi
Chikungunya
Viral disease transmitted
to humans by infected
mosquitoes (Aedes
aegypti)
Onchocerciasis
Parasitic disease
caused by the filarial
worm Onchocerca
volvulus
Yellow fever
Viral disease
transmitted via aedes
mosquitoes
Malaria
Disease caused by a
parasite plasmodium,
transmitted via
infected mosquitoes
Dengue Fever
Mosquito-borne
infection that may
cause lethal
complications
Lymphatic filariasis
Infection occurs when
filarial parasites are
transmitted to humans
through mosquitoes
Dracunculiasis
Infection caused by
drinking-water
containing water fleas
that have ingested
Dracunculus larvae
Lyme Disease
Disease caused by
infected ticks (Ixodes)
Human African
Trypanasomiasis
Glossina-borne parasitic
infection, fatal without
prompt diagnosis and
treatment
Leishmaniasis
Infection is caused if
bitten by female
sandflies
MALARIA
• Anopheles
• Plasmodium falciparum, P. vivax, P. ovale and
P. malariae
• Incubation: 10 days- 4 weeks (7
days-1 year)
• P. vivax and P. ovale—relapsing
malaria–dormant in liver up to 4
years
CCHF
• Family: Bunyaviridae
• Type: Nairovirus
• Crimean-Congo hemorrhagic fever virus

Mortality 5-30%
• Transmission: Tick bite (Hyalomma),
contaminated blood exposure
• The virus is primarily transmitted to people
from ticks and livestock animals.
• Human-to-human transmission can occur
resulting from close contact with the blood,
secretions, organs or other bodily fluids of
infected persons.
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Hyalomma
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Incubation: 1- 13 days (9 days after tick bite)
Fever, myalgia, fatique, head ache, bleeding
Thrombocytopenia, leucopenia,
Increased AST, ALT, CK, LDH
 Petechia, echimosis
 Gum bleeding
 Hemoptysis
 Hematemesis
 Melena, Hematuria, nose bleeding, vaginal bleeding
 Bleeding around/in visseral organs
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THERAPY
General suppotive care
Blood, erytrocyte, platelets, FFP
Ribavirin?
Prevention and control
• Reducing the risk of tick-to-human transmission:
– wear protective clothing (long sleeves, long trousers);
– wear light coloured clothing to allow easy detection of
ticks on the clothes;
– use approved acaricides (chemicals intended to kill ticks)
on clothing;
– use approved repellent on the skin and clothing;
– regularly examine clothing and skin for ticks; if found,
remove them safely;
– seek to eliminate or control tick infestations on animals
or in stables and barns; and
– avoid areas where ticks are abundant and seasons when
they are most active.
WHO 2013
• Reducing the risk of animal-to-human transmission:
– wear gloves and other protective clothing while handling
animals or their tissues in endemic areas, notably during
slaughtering, butchering and culling procedures in
slaughterhouses or at home;
– quarantine animals before they enter slaughterhouses or
routinely treat animals with pesticides two weeks prior to
slaughter.
• Reducing the risk of human-to-human transmission in
the community:
– avoid close physical contact with CCHF-infected people;
– wear gloves and protective equipment when taking care
of ill people;
– wash hands regularly after caring for or visiting ill people.
WHO 2013
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West nile virus
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Family Flaviviridae
Genus Flavivirus
Mosquitoes are the principal vector of WNV.
The virus has been isolated from more than 40
mosquito species, but the predominant genus is
Culex.
• Wild birds are the principal host
• Humans and horses are accidental dead-end
hosts.
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Şekil 1. Batı Nil Virüsü’nün yaşam döngüsü
(Pfeffer M, Dobler G. Emergence of zoonotic arboviruses by animal trade and migration. Parasit
Vectors. 2010 Apr 8;3(1):35.)
Şekil 3. Batı Nil Virüs enfeksiyonunun klinik seyri
•
About 1 in 5 people who are infected will develop a fever with other
symptoms such as
– headache, body aches, joint pains, vomiting, diarrhea, or rash.
•
Most people with this type of West Nile virus disease recover completely, but fatigue
and weakness can last for weeks or months.
•
The symptoms of neurologic illness can include headache, high fever,
neck stiffness, disorientation, coma, tremors, seizures, or paralysis.
•
People with certain medical conditions, such as cancer, diabetes,
hypertension and kidney disease are also at greater risk for serious
illness.
•
Recovery from severe disease may take several weeks or months. Some
of the neurologic effects may be permanent.
•
About 10 percent of people who develop neurologic infection due to
West Nile virus will die.
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• No vaccine or specific antiviral treatments for
West Nile virus infection are available.
• Pain relievers can be used to reduce fever and
relieve some symptoms
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LYME
Lyme disease is caused by the bacterium Borrelia burgdorferi and is
transmitted to humans through the bite of infected blacklegged ticks
(Ixodes)
Ticks can attach to any part of the human body
but are often found in hard-to-see areas such as
the groin, armpits, and scalp.
In most cases, the tick must be attached for 3648 hours or more before the Lyme disease
bacterium can be transmitted.
Early localized stage (3-30 days post-tick bite)
Red, expanding rash --- erythema migrans (EM)
Fatigue, chills, fever, headache, muscle and joint
aches, and swollen lymph nodes
Erythema migrans (EM)
or "bull's-eye" rash
•Rash occurs in approximately 70-80% of
infected persons and begins at the site of a
tick bite after a delay of 3-30 days (average is
about 7 days).
•Rash gradually expands over a period of
several days, and can reach up to 12 inches
(30 cm) across. Parts of the rash may clear
as it enlarges, resulting in a “bull's-eye”
appearance.
•EM lesions may appear on any area of the
body.
Early disseminated stage (days to weeks post-tick bite)
Additional EM lesions in other areas of the body
Facial or Bell's palsy (loss of muscle tone on one or both sides of
the face)
Severe headaches and neck stiffness due to meningitis
Pain and swelling in the large joints (such as knees)
Bell's (facial) palsy
Loss of muscle tone on
one or both sides of the
face is called facial or
“Bell's” palsy.
Late disseminated stage (months to years post-tick bite)
Approximately 60% of patients with untreated infection may
begin to have intermittent bouts of arthritis, with severe joint
pain and swelling.
Up to 5% of untreated patients may develop chronic
neurological complaints months to years after infection.
These include shooting pains, numbness or tingling in the
hands or feet, and problems with short-term memory.
Arthritis
Pain and swelling in the
large joints (such as
knees) can occur.
Dengue is a disease caused by any one of four closely related
dengue viruses (DENV 1, DENV 2, DENV 3, or DENV 4).
The viruses are transmitted to humans by the bite of an infected
mosquito.
• In the Western Hemisphere, the Aedes aegypti
mosquito is the most important vector of dengue
viruses.
• It is estimated that there are over 100 million cases
of dengue worldwide each year.
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Fever, nausea, vomiting, rash
Aches and pains
Leukopenia
Severe plasma leakage
Impaired consciousness
Failure of heart and other organs
……..
Early recognition and prompt supportive
treatment
Yellow fever
• Yellow fever virus is found in tropical and
subtropical areas in South America and Africa.
• Acute viral haemorrhagic disease
• The virus is transmitted to humans by the bite
of an infected mosquito Aedes Aegypti
• Vaccine is available
Map is from the following publication: Jentes ES. Poumerol G, Gershman MD, et al. The
revised global yellow fever risk map and recommendations for vaccination, 2010:
consensus of the Informal WHO Working Group on Geographic Risk for Yellow Fever.
Lancet Infect Dis. 2011;11:622-32.
The "yellow" in the name refers to the jaundice that affects some
patients.
Up to 50% of severely affected persons without treatment will die
from yellow fever.
There are an estimated 200 000 cases of yellow fever, causing 30
000 deaths, worldwide each year, with 90% occurring in Africa.
WHO
There is no specific treatment for yellow fever. Treatment
is symptomatic, aimed at reducing the symptoms for the
comfort of the patient.
Vaccination is the most important preventive measure
against yellow fever.
The vaccine is safe, affordable and highly effective, and a
single dose of yellow fever vaccine is sufficient to confer
sustained immunity and life-long protection against yellow
fever disease and a booster dose of yellow fever vaccine is
not needed.
The vaccine provides effective immunity within 30 days for
99% of persons vaccinated.