NYC health department investigates Legionnaires' disease cluster on Upper East Side

New York City health officials are investigating a cluster of Legionnaires’ disease that has affected residents of the Carnegie Hill and Yorkville neighborhoods on the Upper East Side. As of July 6, the city has recorded 23 cases, 17 of which required hospitalization, and no deaths have been reported.

The agency believes the bacteria responsible for the pneumonia originated from one or more cooling towers in the area, structures that regulate temperature for building systems such as refrigeration. All cooling towers within ZIP codes 10028, 10128 and 10075 are being tested, officials said.

"Because it’s not caused by an issue with any building’s plumbing system, residents can continue drinking tap water, bathing, showering, cooking and using air conditioners," the health department explained.

The disease spreads through inhalation of tiny water droplets containing Legionella bacteria, which thrive in warm water found in places like showerheads, hot tubs and cooling towers. Symptoms typically appear two to 14 days after exposure and include cough, fever, headache, muscle aches and shortness of breath. People aged 50 or older, smokers, those with chronic lung disease or weakened immune systems are at higher risk.

Health officials urged anyone who lives in or has recently visited the affected neighborhoods and experiences flu-like symptoms to contact a health-care provider promptly. The city also provided guidance for building owners to clean and disinfect cooling towers, maintain proper chlorine levels in pools and spas, and regularly flush unused taps.

The Centers for Disease Control and Prevention notes that about one in ten infected individuals may die without timely treatment, underscoring the importance of early diagnosis and antibiotic therapy.