NEW YORK — Two people living on the Upper East Side have been diagnosed with Legionnaires’ disease, city health officials said Friday as they identified two neighborhoods where the deadly bacteria may be spreading.

The patients were found in the Yorkville and Carnegie Hill neighborhoods of the Upper East Side, in zip codes 10028 and 10128, city officials said.

Other potential cases are awaiting confirmation.

Despite the cluster being investigated, it is safe to use your air conditioners during the oppressive heat wave hitting the city, officials said.

Legionnaires’ disease killed seven people and left 90 hospitalized following an outbreak in Harlem last year. During a similar outbreak in the South Bronx in 2015, a dozen New Yorkers were killed. Another 127 were sickened, officials said.

Adults with any flu-like symptoms, fever, cough, or difficulty breathing in the affected areas since late June are encouraged to seek immediate medical attention, officials said. A Health Alert is also going out to healthcare providers throughout the cluster areas, advising them to consider Legionnaire’s disease for people presenting with compatible symptoms.

Community outreach will be conducted in the area beginning over the weekend.

“Any New Yorkers with flu-like symptoms who live, work, or visited the affected area since late June should contact a health care provider as soon as possible,” NYC Health Commissioner Dr. Alister Martin said late Friday. “Legionnaires’ disease is deadly but can be effectively treated if diagnosed early. New Yorkers at higher risk, including anyone who is 50 and older, those who smoke, or people with chronic lung conditions, should be especially mindful of their symptoms and seek care as soon as symptoms begin.”

People only get sick by breathing in water vapor containing Legionella bacteria, officials said. Symptoms resemble other types of pneumonia and can include fever, chills, muscle aches, and cough.

Legionnaires is a bacterial pneumonia caused by the bacteria legionella, which grows in warm water. While it cannot be passed from person to person. Most people exposed to the bacteria do not develop the disease, officials said.

NYC Health Department staffers are sampling and testing water from all cooling tower systems in the cluster area, officials said. Past community clusters have been caused by legionella bacteria spreading through the air from the mist produced by cooling towers.

Building owners with any cooling towers that test positive for the presence of Legionella bacteria will be directed to conduct full remediation.

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