We mapped every UES cooling tower in the area affected by NYC’s latest Legionnaires’ outbreak

Key Points:

• New York City health officials are investigating a cluster of Legionnaires’ disease cases on the Upper East Side, with Mayor Zohran Mamdani pledging to publish locations of cooling towers testing positive for Legionella bacteria promptly.
• Cooling towers, often hidden atop buildings, are part of air conditioning systems and can harbor Legionella bacteria, especially in hot weather, which can spread through water mist and cause pneumonia when inhaled.
• Analysis shows discrepancies in the number of registered cooling towers in affected ZIP codes, with only 55% having reported Legionella test results in 2026, and about half not inspected by the city for over a year, highlighting compliance and inspection challenges.
• Residents are advised to inquire with building owners about cooling tower testing and maintenance, though experts note that proximity to a specific tower does not necessarily increase individual risk due to the bacteria's ability to travel through mist.
• As of the latest update, 36 cases and 22 hospitalizations have been reported, with elderly and immunocompromised individuals at higher risk; cooling towers testing positive must be cleaned and disinfected, though PCR tests may detect non-viable bacteria.