There are now 225 confirmed case of A/H1N1 flu in the US state Illinois, the Department of Public Health of the state said in a press release on Wednesday.

According to officials of the department, the dramatic climb into triple digits over a few days was attributed to the fact that the state labs tackling test backlogs are able for the first time to conduct confirmation tests without sending them away.

Chicago remains the epicenter of the flu outbreak in Illinois, with 93 confirmed cases. Suburban Cook County, about 25 kilometers south of Chicago, has another 57 confirmed cases, and the rest of the confirmed cases were reported in nine other counties.

An additional 20 probable but unconfirmed cases were reported in at least eight counties, the Public Health Department said.