The Illinois Department of Veterans Affairs and the Illinois Department of Public Health are reviewing the case of the resident with the flu-like illness. Officials say the resident of the home 312 miles southwest of Chicago has received medical treatment and is recovering.
Officials say no other cases of the illness contracted by breathing infected water vapor have been identified.
Staff members are monitoring residents for respiratory illnesses. Officials have notified residents, staff members, and relations and representatives of residents.
The last case of Legionnaires' at Quincy was in 2018. An outbreak that began in 2015 caused the deaths of 13 residents and sickened dozens more.
Then-Gov. Bruce Rauner faced withering criticism for not doing enough in response to the crisis.