The Illinois Department of Public Health (IDPH) and the Chicago Department of Public Health (CDPH) are investigating cases of Legionnaires’ disease at two separate nursing homes in Chicago. Two residents at Balmoral Nursing Home and one resident at Admiral at the Lake have been diagnosed with Legionnaires’ disease. The cases at the two facilities do not appear to be related. Residents at each of the nursing homes were at the facility for the entire 10 days before they started showing symptoms, also known as the exposure period. Balmoral Nursing Home has implemented water restrictions and installed water filters in certain areas of the facility. IDPH has collected water samples for testing and is awaiting results. Water samples collected by the facility and tested by its consultant were negative for Legionella bacteria. The facility has provided verbal and written notification to residents and employees. The facility is also conducting surveillance to identify other potential cases and to ensure appropriate testing and clinical management. Admiral at the Lake is in the process of informing residents and staff about the Legionnaires’ disease case and will work to identify other potential cases while implementing appropriate testing and clinical management. IDPH environmental health staff conducted an onsite visit and is coordinating with CDPH and the Chicago Department of Water Management. The facility is implementing processes to reduce exposure and has hired, and been working with, a water management company.