Health officials investigating Legionnaires’ disease cluster

(Minnesota Department of Health) – The Minnesota Department of Health is investigating a cluster of five confirmed cases of Legionnaires’ disease among people who live or spent time in Grand Rapids, Minn., during the two weeks before their illness began. The environmental source of the illnesses has not yet been determined.

The five cases, all adults, became ill between the end of April and mid-July. All were hospitalized; to date, no deaths have occurred associated with this cluster.

Legionnaires’ disease is a bacterial pneumonia that people can get after breathing in aerosolized water containing Legionella bacteria. You cannot get Legionnaires’ disease by drinking water that has Legionella. It is not spread from person to person.

MDH is working to identify possible sources of the bacteria and make recommendations for preventing any additional illnesses. Investigations into Legionnaires’ disease clusters can be complex. Past outbreaks have been linked to various environmental water sources such as cooling towers, building plumbing systems, hot tubs and decorative fountains. The key to preventing Legionnaires’ disease is to reduce the risk of Legionella growth and spread in these water systems.

Legionnaires’ disease can be severe, so prompt diagnosis and appropriate antibiotic treatment is important. Common symptoms include fever, chills, cough, shortness of breath, headaches, muscle aches, and fatigue. Other symptoms may include weakness, loss of appetite, confusion, diarrhea, and nausea.

Most people exposed to Legionella bacteria do not develop Legionnaires’ disease. People at increased risk of infection and severe illness include those ages 50 years and older and current or former smokers. Other risk factors include chronic health conditions such as lung, kidney, or liver disease; diabetes; cancer; and conditions and medications that affect the immune system.

“People who have symptoms or are concerned about their health should contact their health care provider,” said Jessica Hancock-Allen, director of the MDH Infectious Disease Epidemiology, Prevention and Control Division.

MDH has asked health care providers to watch for any additional patients with symptoms that might indicate Legionnaires’ disease. MDH is not recommending testing for people who may have been exposed but do not have symptoms.

In 2022, 109 cases of Legionnaires’ disease were reported in Minnesota. Most cases are sporadic and not associated with any cluster or outbreak. More information can be found on the MDH website at Legionellosis (Legionella).