Legionnaires’ Disease Awareness

As part of the City of St. Louis Department of Health’s efforts to ensure optimum health for all, the Department is raising awareness about Legionnaires’ Disease. This illness is a severe form of pneumonia caused by a bacterium known as legionella. The signs and symptoms of this lung infection include cough, fever, shortness of breath, headaches, as well as diarrhea, nausea and confusion.

Although most people who come into contact with the bacterium do not become ill, as recently as August 2020 the Centers for Disease Control and Prevention announced the disease can be fatal in 1 in 10 cases. Between 2016 and 2020, the five-year median total case count for the City of St. Louis was 11 cases compared to 152 cases overall for Missouri.

“The key to reducing the impact of legionella outbreaks is discovering its existence,” says Dr. Fredrick Echols, acting director of health for the City of St. Louis. “Timely diagnosis reduces the risk for large numbers of cases and deaths.”

Legionella bacteria is found naturally in freshwater environments like lakes and streams, but generally do not exist in those settings in large enough numbers to cause disease. The bacteria can also be found in human constructed water systems such as plumbing in large buildings, cooling towers, decorative fountains, and hot tubs. A public health concern exists when the bacteria begins to grow and spread in these systems. Small droplets containing bacteria are transmitted in the air. People become ill when they breathe in the droplets of water in the air that contain the bacteria. Common places for outbreaks include hotels, health care facilities, pools, and congregate living facilities such as nursing homes and independent living facilities.

Individuals who are at increased risk of getting sick include those 50 years of age or older, current and former smokers, as well as individuals with a chronic lung disease, weak immune systems, and with illness such as Cancer, diabetes, kidney and liver failure.

The City of St. Louis Department of Health recommends building owners and property managers consult CDC published voluntary guidelines and American Society of Heating, Refrigerating and Air Conditioning Engineers guidance to assist in preventing Legionella from spreading at their facilities.