A total of nine cases of the disease -- a type of pneumonia caused by Legionella bacteria -- are under investigation by the New Jersey Department of Health.
Hamilton Township initially announced that there were four cases of Legionnaires' a year ago, NJ Advance Media reported.
“There is concern that Legionella may be present in other buildings and homes in the area,” Hamilton and state officials said in a statement.
No other towns served by Trenton Water Works, a public utility, have reported Legionnaires' cases, which can be treated with antibiotics.
“The water is safe to drink, but there are basic precautions that residents can take to help protect themselves – such as regularly flushing water at their taps and maintaining their hot water tank,” Dr. Tina Tan, state epidemiologist, said in a statement released by Hamilton Township.
Legionnaires' disease doesn't spread from person-to-person. The bacteria spreads through airborne mist, such as from industrial air-conditioning units for large buildings. Home air conditioners are not a risk for growing Legionella, officials said.
Adults over 50, smokers and others with weak immune systems or chronic lung disease are most at risk, according to state Health Department officials.
Many people exposed to the bacteria don't develop symptoms. Those who do develop symptoms may experience cough, fever, chills, shortness of breath, muscle aches, headaches, and diarrhea.
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