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West Nile Virus

West Nile Virus is a disease that can cause brain infection, or encephalitis (en-sef-ul-eye-tis). However, the virus causes encephalitis only in rare cases.

Most people who get infected with the virus don't get sick. Others have symptoms like those of a mild flu (fever, headache, and feeling tired).

The virus is spread by mosquitoes. Mosquito season is April through October. Most cases of West Nile virus happen in the late summer or early fall.

How can I get it?

• People can only become infected with the virus by the bite of an infected mosquito. Mosquitoes get the virus from feeding on birds who have it. The mosquitoes then pass the virus on to other birds, animals, and people by biting them.

Can the virus be spread person-to-person? No.

• West Nile virus does not spread from person to person. You can't catch the virus from other people or animals. And you cannot give the virus to someone else. Only mosquitoes can spread it.

What are the symptoms?

• Symptoms include fever, headache, and body aches. Most infections are mild. Sometimes a skin rash and swollen lymph glands go along with the other symptoms. This type of infection is called West Nile Fever.

Rarely, the virus causes a very bad infection with the following:

• headache, high fever, and neck stiffness
• feeling confused
• coma, shaking, and/or jerking or going limp (convulsions)
• muscle weakness and/or not being able to move (paralysis)
• death (Death is rare, but it has happened.)

If you have any of these symptoms, contact your doctor right away.

Who is most at risk?

• People who live in areas where the virus has been found are at risk.
• People over age 50 have the highest risk of getting very sick from the virus.
• People with weak immune systems also have a high risk of getting very sick.

Pregnancy and West Nile Virus

• The virus does not cause any special danger to pregnant women or their babies, as far as we know.

Is there a shot (vaccine) or treatment? No

• There is no vaccine to protect against West Nile virus. And there is no special treatment for the infection. Most people recover completely. Some very bad cases may need a hospital stay.

Can you get tested for the West Nile Virus?  Yes

• On July 9, 2003, the FDA cleared the first test for use as an aid in the clinical laboratory diagnosis of West Nile virus infection. The blood test is intended for use in patients with clinical symptoms consistent with viral encephalitis/meningitis. West Nile virus often presents as a mild infection that clears without further treatment, some patients develop severe infection resulting in neurological disease and even death.

Ways to Protect Yourself

Avoid Mosquito Bites

• Use insect repellent that has permethrin or DEET. (Do not use it on children less than 2 years old. It can bother their eyes and mouth.)
• Read and follow the product directions
• Wear long-sleeved clothes and long pants
• Wash treated clothing before wearing it again.
• Stay indoors during peak mosquito feeding hours (evening or dusk until dawn).
• Install or fix window and door screens.
• Don't wear perfume or cologne when you go outdoors for a long time.
• Check to see if there is a mosquito control program in your area.

Report Dead Birds

• Call your state or local health department if you see any dead birds. You can play an important role in tracking West Nile virus by doing this.

October 2003

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