Associated Press - September 19, 2009 5:14 PM ET

ROCKFORD, Ill. (AP) - Winnebago County in northern Illinois is reporting its first death from the swine flu.

Winnebago County Health Department Administrator Mike Bacon says the death was reported Friday afternoon.

He says the patient was an adult with a chronic medical condition who fell ill during the first week of the month.

The Illinois Department of Public Health says 17 other state residents have died from swine flu, including two pregnant women. The others also had chronic medical conditions.

Swine flu, known more formally as the H1N1 influenza virus, has similar symptoms to seasonal flu. Those symptoms include fevers of at least 100 degrees, coughs, headaches and body aches.

But with swine flu, diarrhea and vomiting also have been reported.

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