NEW YORK (CBSNewYork) – Health officials say one person has died and at least six others have been infected by Legionnaires’ disease in the Lenox Hill area, near Third Avenue and East 70th Street.

Officials say the person who died was in their 90s, and that three of the six others are still hospitalized. The remaining three have already been treated and released.

The outbreak took place in the past 11 days.

As CBS2’s Alice Gainer reported, Health Commissioner Dr. Mary Bassett says the Health Department identified the cluster of Legionnaire’s within a small radius of the area and are attempting to identify the source.

“Because we’re aware of nothing in common with these seven people, except their geography, they don’t share a spa or healthcare, we are concerned that there may be a cooling tower source,” she said.

Officials are focusing on cooling towers in the neighborhood.

“For that reason the health department has taken water samples from all 116 cooling tower systems within half a kilometer, within the neighborhood,” Dr. Bassett said.

CBS2’s Jessica Layton was on the Upper East Side on Friday night, where fliers were being handed out with details on the disease.

“I don’t understand how this could be so widespread and affect people in New York,” Christine Rosa said. 

Council member Ben Kallos was stopping people heading into the subway at 72nd Street and Second Ave to make sure they knew about the Legionnaires’ cases in the neighborhood.

“I’m pretty concerned with what’s going on,” he said.

The city started regular, mandatory inspections of cooling systems after a deadly Legionnaires’ outbreak in the South Bronx two-years-ago. In that case 12 people died.

Upper East Side residents still feel they need more information what’s happening.

“How can we protect ourselves? How is this spreading?” Rosa asked.

Legionnaires’ does not spread from person to person. Those at highest risk are people age 50 or older who smoke cigarettes, have lung disease, or weakened immune systems.

It’s caused by the bacteria legionella, according to the New York City Health Department, most cases can be traced to plumbing systems like cooling towers, whirlpool spas, hot tubs, humidifiers, hot water tanks, and large air conditioning systems.

The Health Department noted that Legionnaires’ cannot be spread person to person, and those at high risk are people 50 and older with respiratory issues.

Symptoms include fever, cough, chills, muscle aches, headache, fatigue, loss of appetite, confusion and diarrhea, officials said. Symptoms typically appear 2-10 days after exposure to Legionella bacteria.

“I urge individuals in this area with respiratory symptoms to seek medical attention right away,” Bassett said.

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