West Nile Virus WNV
West Nile Virus is transmitted to humans through the bite of an infected mosquito. Mild cases of West Nile infection (West Nile fever) may include a slight fever and head and body aches. Severe infections (West Nile encephalitis) may also include muscle weakness and may progress to encephalitis or meningitis.
Symptoms usually occur three to 14 days after exposure. There is no specific treatment for viral infections, other than to treat the symptoms and provide supportive care. Persons over the age of 50 are at highest risk of becoming seriously ill from West Nile infection. Healthy children and adults are at low risk for serious illness from West Nile virus. Horses are susceptible to WNV infection and should be vaccinated.
West Nile virus is the most common mosquito-borne disease in the U.S. It can be spread by the Culex pipiens mosquito, also known as the northern house mosquito, which is common in Suffolk County.
West Nile Virus in Suffolk County
||Mosquito Samples Testing Positive
* Number in parentheses indicates number of deaths
Chikungunya, Dengue & Zika Virus
Dengue, Chikungunya and Zika viruses are spread primarily by Aedes mosquitoes. Aedes mosquitoes will bite anytime during the day or night. The vast majority of these infections are acquired while traveling to other countries.
Globally, dengue is the most common mosquito-borne disease. In the U.S., outbreaks of dengue have occurred in the south and Hawaii, with only one locally acquired infection having been reported in Suffolk County.
Chikungunya outbreaks have occurred throughout Asia, Africa and Europe, and more recently in the Caribbean. No locally acquired infections have been reported in Suffolk County.
In addition to the bite of an infected mosquito, Zika virus can also be spread through sexual contact or blood transfusions. It can also be passed from mother to fetus during pregnancy. Infection during pregnancy can cause certain birth defects. Zika virus outbreaks have occurred in parts of Africa, South and Central America, Mexico and the Caribbean. No locally acquired infections have been reported in Suffolk County.
Click here for more information about Zika virus.
Travel: Precautions should be taken when traveling to places where these viruses are circulating. Visit the CDC’s website for current information on at risk travel destinations.
More about Aedes Mosquitoes: According to the CDC, Aedes aegypti mosquitoes are more capable of spreading viruses than Aedes albopictus (also known as Asian Tiger) mosquitoes.
- Currently, Aedes aegypti mosquitoes are not found in New York.
- Aedes albopictus mosquitoes have been found in Suffolk County since 2004.
- Aedes albopictus mosquitoes have not been known to cause infection in Suffolk County, but are capable of transmitting viruses and have been implicated in outbreaks in other countries.
Eastern Equine Encephalitis (EEE)
Eastern equine encephalitis virus (EEEV) is transmitted to
humans through the bite of an infected mosquito. Eastern equine encephalitis
(EEE) is a rare illness in humans, and only a few cases are reported in the
United States each year.
Equine Encephalitis virus is typically spread by a variety of mosquitoes from
swampy regions. In Suffolk County, this virus has been found sporadically
in mosquitoes but there has never been a human infection.
Most persons infected with EEEV have no
apparent illness. Severe cases of EEE (involving encephalitis, an inflammation
of the brain) begin with the sudden onset of headache, high fever, chills and
vomiting. The illness may then progress into disorientation, seizures, or coma.
EEE is one of the most severe mosquito-transmitted diseases in the United
States with approximately 33 percent mortality and significant brain damage in
There is no specific treatment for EEE;
care is based on symptoms. You can reduce your risk of being infected with EEEV
by using insect repellent, wearing protective clothing, and staying indoors
while mosquitoes are most active. If you think you or a family member may have
EEE, it is important to consult your healthcare provider for proper diagnosis.
Horses are susceptible to EEEV infection and should be vaccinated.