JEFFERSON CITY, Mo. — Health officials are working to determine how four people contracted Legionnaire’s disease while hospitalized last year at Phelps Health in Rolla, the state health department announced Tuesday.

The four patients were hospitalized between May and December of last year, the Missouri Department of Health and Senior Services said.

The health department said it is advising health care workers and the public who might have had contact with a water source at the hospital about the cases “out of an abundance of caution.”

Legionnaire’s disease is a serious type of pneumonia caused by inhaling small water droplets containing legionella bacteria. It is generally not spread from person to person.

The health department is collaborating with Phelps Health to prevent additional infections and ensure early detection of cases, Dr. George Turabelidze, state epidemiologist, said in a news release.

Phelps Health is also working with its water monitoring company for continued testing of its water system, and is contacting providers about the possibility of legionella transmission.

“At Phelps Health, the health and safety of our patients, visitors and staff are our top priorities,” Phelps Health President and CEO Jason Shenefield said. “We will continue collaborating with our partners to help investigate these cases.”

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