West Nile Virus

West Nile Virus (WNV) is one of a group of disease-causing viruses spread by mosquitoes. It first appeared in the United States in 1999. The virus is transmitted to humans and animals through the bite of an infected mosquito. Mosquitoes become infected with WNV when they feed on infected birds.

Most people who are bitten by a mosquito with WNV will not get sick. People who do become ill may experience flu-like symptoms such as a fever, headache and body ache. Approximately, one in five people bitten by an infected mosquito will become ill. Less than one percent of infected individuals require hospitalization. The elderly and the immune-compromised are most susceptible to illness caused by WNV.

What are the symptoms of West Nile Virus?

Studies have shown that only a small percentage of infected humans show symptoms of disease.

Symptoms of West Nile fever, resulting from infection with West Nile virus, include fever,headache, rash, and aches. In severe cases,encephalitis, meningitis,may occur. Severe symptoms may include high fever, disorientation,tremors, coma, paralysis,and death.

The time between the mosquito bite and the onset of illness,known as the incubation period, ranges from 5-15 days in humans.

How do people and animals get West Nile Virus?

West Nile virus is transmitted from bites by a mosquito infected with WNV. Only 62 of the 176 species of mosquitoes have been found infected with WNV during testing, however only very few of these species are actually involved with disease transmission. A mosquito becomes infected by feeding on a wild bird that has WNV in its blood. The mosquito then transmits the WNV in its saliva when it bites a person or animal.

Is there a cure for West Nile Virus?

There is no current vaccine or cure for West Nile fever. Please contact your physician if you think you or a family member may have been exposed to WNV.

Why is it important to report a dead bird?

Certain species of birds, especially crows, jays,hawks, ravens, gulls, pigeons, ducks,owls,sparrows, and finches are highly susceptible to WNV. Dead birds can be the first indication of virus transmission in an area. If you find a bird that has recently died with no obvious cause, please call your local health department.

How can you protect yourself?

Avoid outdoor activity at dawn and dusk during the mosquito season.

Avoid shaded areas where mosquitoes may be resting.

If you need to be outside, wear protective clothing such as loose-fitting, lightcolored,

long-sleeved shirts and pants.

Clean up any standing water in your yard that might breed mosquitoes (clogged gutters, tires, buckets, bird baths,etc..)

Check for holes or tears in window and door screens.

Use mosquito trap, mosquito repellents. Choose a mosquito repellent that has been recommended by the Centers for Disease Control and Prevention and has been registered by the Environmental Protection Agency.

Registered products have been reviewed for efficacy and pose minimal risk for

human safety when used according to label directions. Three repellents that are approved and recommended are:

  -DEET (N,N-diethyl-m-toluamide)

  -Picaridin (KBR 3023)

  -Oil of lemon eucalyptus (pmethane

    3,8-diol, or PMD).

How do I report a mosquito problem in my area?

Call your local mosquito control district or county health department. Many states have mosquito control districts on a county or regional level.