West Nile Virus

Report within 24 hours of Diagnosis to the Local Health Department.

West Nile virus is an infection that is spread by the bite of an infected mosquito. Identified in the United States in 1999, West Nile virus is seen most often during the summer and early fall months. Anyone can get infected with West Nile virus. People over age 50 and people with weak immune systems are at greater risk of developing severe illness. Mild symptoms are flu-like and may include fever, headache, body aches and sometimes a rash. Severe symptoms can include high fever, stiff neck and swelling of the brain. There is no specific treatment for West Nile virus. The best way to prevent the disease is to avoid mosquito bites.


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Education Materials
Laboratory Testing and Guidance

Clinicians requesting West Nile virus testing should complete the Arboviral Testing Request worksheet and send via encrypted e-mail to CDSVectorTeam@doh.nj.gov

NEW (July 2021) A morbidity/mortality event has been occurring in nestling and fledgling songbirds in the mid-Atlantic, extending into the Southeast and eastern upper Midwest. Since mid-May, numerous young birds - mainly blue jays, starlings, and common grackles, but also robins and cardinals - have been found with eye and neurologic issues, and in some cases these birds have been found dead in large numbers. Cases have been reported in many states, including New Jersey. Many theories have been posed as to the cause of this event, however no cause has been determined at this time. The New Jersey Department of Environmental Protection (NJDEP) Division of Fish and Wildlife is investigating these reports. For more information, recommendations, and to report an ill or dead songbird, go to the NJDEP Division of Fish & Wildlife’s webpage.

Routine bird testing for WNV has been discontinued, but it is still recommended to report dead or ill birds to the county mosquito control agency; testing birds for WNV remains available by special request.

Last Reviewed: 8/24/2021