The illnesses involve people who visited Skokie Country Club in Glencoe. Health officials are still trying to identify the source of the bacteria.
Officials say there are 29 confirmed salmonella cases. Seven of those people remain hospitalized.
The health department says it's following up on more than 50 additional reports of gastrointestinal illness from people who ate at the club.
The country club says it has voluntarily closed its kitchen. But the golf course, tennis courts and pool remain open.