(NEW YORK) — Health officials in New York City said they are investigating a cluster of Legionnaires’ disease.
As of July 6, 23 cases of Legionnaires’ disease have been confirmed in two of Manhattan’s Upper East Side neighborhoods, according to the New York City Department of Health. So far, no deaths have been associated with the cluster.
In a notice to the two neighborhoods — Carnegie Hill and Yorkville — the department said it believes the likely source of the bacteria is a cooling tower in the area, which sprays a mist that contains the bacteria.
The health department said there is no issue with any building’s plumbing system and that residents in the affected areas can continue to drink tap water, bathe, shower, cook and use their air conditioners.
“All cooling towers in [the] area are being sampled and tested in the NYC Public Health Lab,” Mark Levine, the city’s comptroller, wrote in a post on X on Sunday evening. “It unfortunately takes several weeks for cultures to grow.”
Legionnaires’ disease is a severe form of pneumonia caused by inhaling the Legionella bacteria in small droplets of water mixed in the air or contaminated water accidentally going into the lungs.
The bacteria are found naturally in freshwater but amounts generally don’t lead to disease. The bacteria typically grow best in warm water and in warm to hot temperatures, according to the Centers for Disease Control and Prevention (CDC).
The disease does not generally spread from person to person, but infections can occur if the bacteria get into a building’s water supply, including in shower heads, sink faucets, hot water tanks, heaters, cooling towers and other plumbing systems.
Legionnaires’ disease has increased in prevalence over the last decade, reaching a peak of 2.71 cases per 100,000 in 2018, the CDC said. Cases dropped during the first year of the COVID-19 pandemic and then rebounded in 2021.
Although most people recover from Legionnaires’ disease with antibiotics, certain patients — including those who are immunocompromised or who suffer from chronic lung diseases — can develop complications that can be fatal.
About one out of every 10 people who develop Legionnaires’ disease will die due to complications, according to the CDC. Among those who develop Legionnaires’ disease during a stay in a healthcare facility, about one out of every four people will die, the federal health agency added.
The NYC health department said anyone who lives or works in the affected areas — or has visited since late June — and is experiencing flu-like symptoms should contact a healthcare provider immediately. The ZIP codes for the areas are 10028, 10128, and 10075.
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