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West Nile Encephalitis (cont.)

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When is there an increased risk for infection?

The risk of infection is highest during mosquito season and does not lower until mosquito activity ceases for the season (when freezing temperatures occur). In temperate areas of the world, cases of West Nile virus infection occur primarily in the late summer or early fall. In southern climates where temperatures are milder, West Nile virus infections can occur year round.

Who is at risk for getting West Nile virus?

All residents of areas where active cases have been identified are at risk of developing West Nile virus infection. People who are 50 years of age or older have the highest risk for more severe cases.

The American Academy of Pediatrics states children appear to be at low risk for the disease, although the youngest person in New York to become seriously ill was 5 years old.

What is the treatment for West Nile virus? Can West Nile virus be prevented with a vaccine?

The diagnosis of West Nile virus infection is confirmed with a blood or cerebrospinal fluid test. There is no specific treatment for West Nile virus infection. Intensive supportive therapy is directed toward the complications of brain infections. Anti-inflammatory medications, intravenous fluids, and intensive medical monitoring may be required in severe cases. There is no specific antibiotic or antidote for the viral infection. There is no vaccine to prevent the virus.

Is a woman's pregnancy at risk if she gets West Nile virus?

There is no clear evidence that a pregnancy is at risk due to infection with West Nile virus. However, the CDC states that in 2002, one case of transplacental (mother-to-child) transmission of West Nile virus was reported. In this case, the infant was born with West Nile virus infection and severe medical problems. In 2003 and 2004, a CDC registry identified 77 women who acquired West Nile virus illness while pregnant. Seventy-one of these women delivered live infants, two had elective abortions, and four miscarried in the first trimester. The CDC is continuing to gather research and outcome data for pregnancies of West Nile virus-infected mothers.

Due to concerns that mother-to-child West Nile virus transmission can occur, the CDC recommends that pregnant women take precautions to reduce their risk for West Nile virus and other mosquito-borne infections. Pregnant women who become ill should see their health-care professional, and those who have an illness consistent with acute West Nile virus infection should undergo appropriate diagnostic testing.

Medically Reviewed by a Doctor on 10/15/2014

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West Nile Virus - Cause Question: How did you get West Nile virus? Were you traveling when you became ill?
West Nile Virus - Treatment Question: What kinds of treatment, including medication, did you or someone you know receive for West Nile virus?
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