The New Jersey Department of Health is investigating an increase in Legionnaires’ disease cases in Middlesex and Union counties.

Officials say that as of Nov. 6, about 40 people tested positive for Legionella, the bacteria that causes the illness. The department is collaborating with local agencies to investigate the cases and any potential sources of infection.

"The concern is there might be something out there that is exposing these people to these infected waterdrops. That's what happens because you have to breathe in these water drops,” says Ed Lifshitz, medical director of the Communicable Disease Service at the Health Department. “This is a serious illness, but it is also treatable. We don't want people thinking, ‘Maybe it’s the flu, maybe its COVID, we’re just going to ride it out.’"

Symptoms of the illness include fever, chills, shortness of breath, chest pain, muscle aches and headache. The diseases cannot be passed from person to person.