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West Nile virus

What are the Symptoms?

It is impossible to tell from a mosquito bite on the skin surface whether the mosquito was carrying an infection such as West Nile virus. Research indicates that approximately four out of five people who are bitten by an infected mosquito do not show any symptoms. While most people who become infected will experience no symptoms or have very mild illness, for some the symptoms will be pronounced. For a very rare few, the virus causes serious neurological illness such as encephalitis.

Your physician has the information available to determine if you need to be tested for West Nile virus.

If you have any of the following symptoms, seek medical help. These may be early symptoms of West
Nile virus illness, or of many other illnesses, so seek medical attention to find out the cause.

Extreme swelling or infection at the site of the mosquito bite is another reason to seek medical attention. This may or may not indicate West Nile virus infection.

If you have concerns, ask your physician.

How does the virus spread?

West Nile virus is spread to humans by the bite of an infected mosquito. Mosquitoes usually become infected when they bite an infected bird.

Who is at risk?

Everyone who is active and outside during the summer months, such as gardening, golfing, walking or
camping, is at risk.

Make sure you use all the protection measures to avoid contact with mosquitoes.

If you like to work outside, avoid early morning and evening when mosquitoes are most active.

For More Information

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