Mosquitoes with West Nile virus identified in Genoa after found in DeKalb, Sycamore

DeKalb County Health Department reports positive samples since August are first in DeKalb County since 2019

The DeKalb County Health Department reported Monday mosquitoes collected in a trap in Genoa have tested positive for the West Nile virus for the first time this year, while the DeKalb and Sycamore traps continue to test positive for the virus.

There have been no human cases in DeKalb County this year, officials said. However, there have been eight human cases reported so far in Illinois this year.

Thirty-nine counties in the state reported West Nile positive mosquito samples this year. The samples are associated with an increased risk of West Nile virus in people, according to the news release.

The update comes after mosquitoes collected in traps in DeKalb and Sycamore tested positive for the West Nile virus less than a month ago. That was the first time samples in the county tested positive since 2019, according to an Aug. 27 announcement by the DeKalb County Health Department.

West Nile virus is transmitted through the bite of an infected mosquito. Mosquitoes become infected after feeding on an infected bird. It is important to remember that not all mosquitoes, or birds, carry West Nile virus. Most do not.

Symptoms to watch for

Most people with the virus have no clinical symptoms of illness, but some may become ill three to 14 days after the bite of an infected mosquito. Illness from West Nile is usually mild and includes fever, headache and body aches, but more serious illness, including encephalitis and meningitis, have been known to develop. People older than 50 years of age have the highest risk of severe disease.

“The most effective way to prevent you or your family from being infected is to reduce the chances of being bitten by mosquitoes,” Greg Maurice, director of health protection, said in a statement. “This includes eliminating standing water from around your house and using mosquito repellent when outside.”

Maurice offers these tips, according to the Monday release:

• Avoid being outdoors when mosquitoes are most active, especially between dusk and dawn.

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

• 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.

• Change water in birdbaths weekly. Properly maintain wading pools and stock ornamental ponds with fish. Turn over any buckets, garbage cans, or other containers that collect water.

For information, check the DeKalb County Health Department website at

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