First West Nile Virus Positive Mosquitoes in Southern Illinois for 2013 Reported

The Illinois Department of Public Health (IDPH) has confirmed the first West Nile virus positive mosquito batches reported in southern Illinois for 2013. 

IDPH collected a positive mosquito sample on June 24 from Tamaroa in Perry County and the East Side Health District collected a positive mosquito sample on June 24 from East St. Louis in St. Clair County.

“As temperatures rise we are starting to see West Nile virus in mosquitoes,” said Illinois Department of Public Health Director Dr. LaMar Hasbrouck.  “Remember to protect yourself by wearing insect repellent and getting rid of any standing water around your home.”    

A mosquito sample collected in Cook County in May was the first West Nile virus positive result this year.  Cook, DuPage, McHenry and now Perry County are reporting West Nile virus positive mosquitoes so far this season. 

The first West Nile virus positive result in 2012 was a crow collected by the Chicago Department of Public Health on May 16, 2012.  Last year, 55 counties in Illinois reported a West Nile virus positive mosquito batch, bird and/or human case. 

For the 2012 season, IDPH reported the second highest number of West Nile virus human cases in state history with 290 residents and 12 deaths.  This was second only to the 2002 outbreak in Illinois in which 884 residents contracted West Nile disease and 67 died.  No human cases of West Nile virus have been reported so far this year.

Surveillance for West Nile virus in Illinois includes laboratory tests on mosquito batches, dead crows, blue jays, robins and other perching birds, as well as testing sick horses and humans with West Nile-like disease symptoms.  People who observe a sick or dying crow, blue jay, robin or other perching bird should contact their local health department, which will determine if the bird will be picked up for testing.

West Nile virus is transmitted through the bite of a mosquito that has picked up the virus by feeding on an infected bird.  Common West Nile virus symptoms include fever, nausea, headache and muscle aches.  Symptoms may last from a few days to a few weeks.  However, four out of five people infected with West Nile virus will not show any symptoms.  In rare cases, severe illness including meningitis or encephalitis, or even death, can occur.  People older than 50 are at higher risk for severe illness from West Nile virus.

The best way to prevent West Nile disease or any other mosquito-borne illness is to reduce the number of mosquitoes around your home and to take personal precautions to avoid mosquito bites.  Precautions include practicing the three “R’s” – reduce, repel and report.

•    REDUCE exposure - avoid being outdoors when mosquitoes are most active, especially between dusk and dawn.  Make sure doors and windows have tight-fitting screens.  Repair or replace screens that have tears or other openings.  Try to keep doors and windows shut, especially at night.  Eliminate all sources of standing water where mosquitoes can breed, including flowerpots, wading pools, old tires and any other receptacles.  Change water in bird baths weekly.  

•    REPEL - when outdoors, wear shoes and socks, long pants and a long-sleeved shirt, and apply insect repellent that contains DEET, picaridin, oil of lemon eucalyptus or IR 3535, according to label instructions.  Consult a physician before using repellents on infants.

•    REPORT - In communities where there are organized mosquito control programs, contact your municipal government to report areas of stagnant water in roadside ditches, flooded yards and similar locations that may produce mosquitoes. Public health officials believe that a hot summer increases mosquito activity and the risk of disease from West Nile virus.

Additional information about West Nile virus can be found on the Illinois Department of Public Health’s Web site at www.idph.state.il.us/envhealth/wnv.htm.