The Illinois Department of Public Health says a 58-year-old man from DuPage County died Wednesday after becoming ill with West Nile encephalitis in mid-August.
The disease, spread by the bite of an infected mosquito, has been reported in 20 people in Illinois this year. The state recorded 54 human cases and one death in 2003 and led the nation with 884 cases and 66 deaths in 2002.
West Nile symptoms usually are mild and can include fever, headache and body aches, but death or serious illness are possible. Only about 20 percent of those bitten by an infected mosquito will become ill.