The number of Legionnaires’ disease cases in an outbreak on Manhattan's Upper East Side has risen to 14, as local health officials continue to search for the source of the potentially fatal pneumonia-like illness. The affected neighborhoods include Carnegie Hill and Yorkville.
The increase marks a sevenfold rise from Thursday, when the New York City Health Department first reported two cases in the area. As of Sunday, 14 individuals had been diagnosed. Residents who have lived, worked, or visited the affected ZIP codes (10028, 10128, and 10075) since late June are advised to contact a healthcare provider if they develop flu-like symptoms such as fever, cough, or difficulty breathing.
Legionnaires' disease is treatable with antibiotics if diagnosed early, but it can be fatal if not addressed promptly. NYC Health Commissioner Dr. Alister Martin stated, "Legionnaires’ disease is deadly but can be effectively treated if diagnosed early." He urged individuals at higher risk, including those aged 50 and older, smokers, and people with chronic lung conditions, to be particularly mindful of their symptoms and seek medical care immediately.
Health officials believe the most probable source of the outbreak is a cooling tower contaminated with Legionella bacteria. Investigations are underway to identify the specific tower responsible. Cooling towers, often located on building rooftops, can aerosolize mist containing the bacteria, which can then be inhaled.
Authorities have begun sampling and testing cooling towers in the vicinity as part of the probe. The health department has reassured the public that the overall risk remains low and that daily activities like bathing, showering, cooking, and using air conditioners are safe. This is particularly important as the city recovers from a recent heat wave.
This outbreak follows a significant Legionnaires' disease event in Harlem last summer, which sickened 114 people, led to 90 hospitalizations, and resulted in seven deaths. In response to that outbreak, the City Council passed legislation requiring building owners to conduct monthly Legionella testing during warmer months when cooling towers are in operation.
No deaths have been reported in connection with the current Upper East Side cluster. For those seeking healthcare providers, regardless of insurance or immigration status, assistance is available by calling 311 or 844-NYC-4NYC (844-692-4692).