First Human West Nile Virus Case for 2013 in Illinois

The Illinois Department of Public Health (IDPH) has confirmed the first human West Nile virus case reported in Illinois for 2013.  The McHenry County Health Department reported a woman in her 50’s became ill earlier this month.

“This first human case is a good reminder that we all need to take precautions,” said Illinois Department of Public Health Director Dr. LaMar Hasbrouck.  “The mosquitoes that typically carry West Nile virus, commonly called the house mosquito, are not as noticeable as the swarms of floodwater mosquitoes we saw in the spring.  Even if it does not look like there are a lot of mosquitoes outdoors, house mosquitoes are stealthy biters so make sure to use insect repellent when you’re outside.”

A mosquito sample collected in Cook County in May was the first West Nile virus positive result this year, and a starling collected in late June in Monroe County was the first positive bird.  To date, West Nile virus positive birds, mosquitoes and/or human case have been reported in 50 counties.

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.  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 water in bird baths, ponds, flowerpots, wading pools, old tires and any other receptacles.  

•    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 dead birds and areas of stagnant water in roadside ditches, flooded yards and similar locations that may produce mosquitoes.

Additional information about West Nile virus can be found on the Illinois Department of Public Health’s website at www.idph.state.il.us/envhealth/wnv.htm.  Surveillance numbers are updated every Wednesday afternoon http://www.idph.state.il.us/envhealth/wnvsurveillance13.htm.