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West Nile Virus Is A Risk You Can Do Something About With A Few Simple Steps.

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Picture of mosquito

WEST NILE VIRUS is now in most of the United States. The most important way people become infected is through the bite of an infected mosquito. You can reduce your chance of getting infected by avoiding mosquito bites.


People over age 50 have a higher risk for becoming seriously ill when they get infected with West Nile virus.
People under age 50 can also become sick, but it is less likely.

Picture of man spraying DEET

Most people who get infected with West Nile virus do not have any symptoms. Some people develop a mild illness called West Nile Fever. This mild illness gets better on its own. No treatment is needed. A small number of people (less than 1 out of 100) who get infected with West Nile virus develop severe disease, called West Nile encephalitis or West Nile meningitis (inflammation of the brain or the area around the brain). This severe disease usually requires hospitalization. In some cases, especially among older persons, it can result in death. Symptoms of severe illness include headache, high fever, stiff neck, mental confusion, muscle weakness, tremors (shaking), convulsions, coma, and paralysis. See your doctor if you develop these symptoms. There is no specific treatment for the West Nile virus infection.

There is no vaccine available for people.

For more information on West Nile Virus:
Check out our Quesions and Answers.


mosquito bullet icon 1 AVOID MOSQUITO BITES!
  • Cover Up! Wearing long sleeve shirts, long pants and socks sprayed with repellent while outdoors can further help prevent mosquito bites. Avoid Mosquitoes! Many mosquitoes bite between dusk and dawn. Limit time outdoors during these hours, or be especially sure to use repellents and protective clothing.
  • Spray! Spray insect repellent containing DEET (Look for N, N-diethyl-m-toluamide) on exposed skin when you go outdoors. Spray clothing with repellents containing DEET or permethrin. Products with a higher percentage of DEET (up to 50%) give longer protection. Don't spray repellent on skin under clothing. Don't use permethrin on skin.
  • Use Repellent Carefully! Repellents containing DEET are very safe for adults and children when used according to directions. Don't put repellent on kid's hands because it may get in their mouth or eyes.
mosquito bullet icon 2


Screens: Keep mosquitoes outside by fixing or installing window and door screens.
Drain Standing Water: Don't give mosquitoes a place to breed. A small amount of standing water can be enough for a mosquito to lay her eggs. Look around every week for possible mosquito breeding places.

Empty water from buckets, cans, pool covers, flower pots and other items. Throw away or cover up stored tires and other items that aren't being used. Clean pet water bowls weekly. Check if rain gutters are clogged. If you store water outside or have a well, make sure it's covered up. Encourage your neighbors to do the same.

mosquito bullet icon 3


Dead birds help health departments track West Nile virus.
Check with local or state health department to find out their policy for reporting dead birds.


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Date last modified: August 1, 2007
Content source:
Division of Vector Borne Infectious Diseases
National Center for Zoonotic, Vector-Borne, and Enteric Diseases

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