First human case of West Nile virus reported in Cook County

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CHICAGO — The Cook County Department of Public Health officials have confirmed the first human case of West Nile virus in suburban Cook County.

The case involved a woman in her 50s from the northwest suburbs, who became ill in late July.

Officials say testing shows that there are pools of mosquitoes carrying WNV in 57 communities in Cook County.

Most people infected with WNV have no symptoms of illness and never become ill, but illness can occur 3-15 days after an infected mosquito bite and cause symptoms of fever, headache and body aches.

The disease can affect all ages, but people over the age of 50 and those with a chronic disease, such as heart disease or cancer, may be at increased risk for serious complications such as encephalitis or meningitis.

For that reason, people who experience high fever, confusion, muscle weakness, severe headaches, or a stiff neck should see a doctor immediately.