Five confirmed cases of Legionnaires’ disease have been reported among people who live or work in the Hopkins area, the Minnesota Department of Health said Friday.

The agency said it is investigating to find the source of the outbreak along with Hennepin County health officials.

The five people became ill between Aug. 4 and Sept. 1, the agency said. Three are currently hospitalized, and two others were hospitalized and have recovered. The patients are all over age 50.

Legionnaires’ disease is spread by inhaling the fine spray from water sources containing Legionella bacteria.

“It is not spread person to person, and you cannot get it by consuming water,” the Health Department said in a news release.

Outbreaks of Legionnaires’ disease have been linked to cooling towers (air-conditioning units for large buildings), cooling misters, decorative fountains or plumbing systems.

Minnesota typically sees 50 to 60 cases of Legionnaires’ disease each year. More than 60 cases have been reported in the state so far this year, mirroring a national increase in cases in 2016. No other clusters have been reported in Minnesota this year.

Most people exposed to Legionella, the bacteria that causes Legionnaires’ disease, don’t get sick. People over 50, smokers or those with certain medical conditions — including weakened immune systems, chronic lung disease or other chronic health conditions — are at increased risk.

Symptoms of Legionnaires’ disease include muscle aches, chills, shortness of breath, headache, fatigue, loss of appetite and coughing. These symptoms may be followed by high fever (102-105°F), pneumonia, and occasionally abdominal pain and diarrhea.