Mosquitos in Oak Lawn, Evergreen Park Test Positive for West Nile

Mosquitos culled from two suburbs in Cook County have tested positive for West Nile Virus, health officials said Thursday.

The batches—pulled from Oak Lawn May 21and Evergreen Park May 26—were the first collected this year in northern Illinois.

“We have confirmed mosquitoes testing positive for West Nile virus from southern Illinois to northern Illinois,” Illinois Department of Public Health Director Nirav D. Shah said Thursday in a release. “Although the county in which you live may not be reporting a West Nile virus positive result, you still need to take precautions, as we’re seeing positive results from across the state.”

Surveillance for the 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 virus-like symptoms.

West Nile virus is transmitted through the bite of a mosquito that has picked up the virus by feeding on an infected bird, the release stated. Common 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. 

To avoid West Nile, health officials recommend residents limit time outside between dusk and dawn, when mosquitoes are most active. Eliminate sources of standing water, and wear long sleeves, pants and mosquito repellent when outside.

Almost 40,000 people in the U.S. have been reported with West Nile virus disease since 1999, and of those over 17,000 have been seriously ill and more than 1600 have died. Many more cases of illness are not reported to CDC.