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West Nile Virus (cont.)

When to Seek Medical Care for West Nile Virus Infection

West Nile virus is transmitted by mosquitoes mainly during the summer months, and infections generally appear between the months of May to October. Rarely, transmission via blood transfusions, organ transplants, and mother-to-fetus or mother-to-infant from breastfeeding has been reported.

  • People who have been bitten by a mosquito in the geographic area where West Nile virus is known to appear and who experience signs or symptoms of serious illness should see their doctor immediately.
  • Most people with mild symptoms of low-grade fever and muscle aches do not have West Nile virus and will not require specific diagnostic testing.

Anyone who has symptoms of severe illness such as mental-status changes, high fever, neck stiffness, sensitivity to light, or confusion should go to an urgent-care center or hospital emergency department immediately. The West Nile encephalitis that occurred during the initial 1999 New York outbreak was especially notable for its severe muscle weakness. This is another important warning symptom.

Medically Reviewed by a Doctor on 4/9/2015

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Read What Your Physician is Reading on Medscape

West Nile Encephalitis »

West Nile encephalitis (WNE) is distinguished from other arthropod-borne causes of viral encephalitis (eg, western equine encephalitis, eastern equine encephalitis [EEE], Japanese encephalitis, Venezuelan encephalitis) based on its geographic distribution, clinical features, and laboratory findings.

Read More on Medscape Reference »

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