The Illinois Department of Public Health (IDPH), working closely with local health departments, has identified two separate clusters of Legionnaires’ disease cases.  One cluster involves residents in McHenry and Lake Counties, while the other involves residents at Warren Barr South Loop nursing home in Chicago.

Legionella bacteria Image/CDC
Legionella bacteria
Image/CDC

“The two recently identified clusters of Legionnaires’ disease are not connected,” said IDPH Director Nirav D. Shah, M.D.  “IDPH is continuing to investigate possible sources, identify other individuals who may have been exposed, and recommend remediation and prevention measures.”

Public health officials identified a slight uptick in September of diagnosed Legionnaires’ disease cases.  IDPH worked with the McHenry County and Lake County health departments and identified the Walmart in Johnsburg as one common potential exposure.  The Walmart location has taken action, including turning off the produce water sprayers.  Health officials will continue to investigate any other potential sources and identify other cases of Legionnaires’ disease.

Illinois: Legionnaires’ Disease cases reported in Champaign County

The second cluster involves two residents of the Warren Barr South Loop nursing home in Chicago.  The nursing home has taken action, including revising its water management plan, increased environmental sampling, and heightened clinical surveillance.  The facility is notifying residents, the residents’ identified contacts, and staff, and following public health recommendations for ongoing surveillance, mitigation, and remediation.

Legionnaires’ disease is a serious lung infection (pneumonia) that people can get by breathing in small droplets of water containing Legionella bacteria.  Outbreaks are most commonly associated with buildings or structures that have complex water systems, like hotels, hospitals, long-term care facilities, and cruise ships.  The bacterium can become a health concern when it grows and spreads in human-made water systems, like hot tubs, cooling towers, hot water tanks, large plumbing systems, and decorative fountains.

Most healthy people do not get Legionnaires’ disease after being exposed to Legionella bacteria.  People at increased risk of Legionnaire’s disease are those 50 years of age or older, or those who have certain risk factors, such as being a current or former smoker, having a chronic disease, or having a weakened immune system.