Health officials have shut down a spa at the LA Fitness location in Naperville.
Authorities with the DuPage County Health Department said disinfectant levels in the spa didn't meet code.
"The facility operator has been cooperating with the health department during ongoing monitoring of the spa," reads a statement on the agency's website.
The club, at 1836 Freedom Dr., was closed briefly in October after two men contracted Legionnaires disease, a severe form of pneumonia that is typically contracted by breathing in a mist or vapor that contains the bacteria. The symptoms typically include coughing, high fever and chills.
The pool and gym will remain open in this latest case.