The NYC Health Department has identified 45 additional buildings with Legionella-positive cooling towers on the Upper east side, bringing the total number of affected sites to 76. This development comes as part of an ongoing investigation into a Legionnaires’ disease outbreak that has sickened 60 people, with 49 requiring hospitalization.
The outbreak, which began in late June, has been linked to cooling towers in the area. These towers, which release water mist into the outside air, can harbor Legionella bacteria the cause of Legionnaires’ disease. The bacteria can be inhaled by passersby, leading to infection.
Citywide response and remediation efforts
City health officials have ordered all building owners with Legionella-positive cooling towers to drain, clean, and disinfect their systems. As of Tuesday, 57 building owners had completed the remediation process, while another 19 were ordered to finish by Thursday. The affected buildings are located in three ZIP codes: 10028, 10128, and 10075, stretching from the East river to Central Park.
Dr. Alister Martin, the city health commissioner, assured residents that there is no additional risk associated with being inside one of these buildings. He also noted that the number of new Legionnaires’ diagnoses has slowed in recent days, after peaking on July 6.
Testing and investigation
The NYC Health Department has conducted PCR testing on over 180 cooling towers in the affected area. While PCR testing can detect the presence of Legionella bacteria, it cannot determine whether the bacteria are alive or dead. To confirm the presence of live bacteria, the department is conducting culture testing which takes up to two weeks.
Under the Mamdani administration, building owners are required to perform a full cleaning and disinfection immediately after a positive PCR screening test, rather than waiting for confirmatory culture test results. This more aggressive strategy aims to eliminate the risk of additional exposure while testing continues.
Notable buildings affected
Among the buildings that have tested positive for Legionella are notable locations such as the Guggenheim Museum at 1071 Fifth Ave. and the prestigious condominium building at 120 E. 87th St. Additionally, a cooling tower for the Second Avenue subway, operated by the MTA, has also tested positive but has already been cleaned.
The investigation into the outbreak began on July 2, after two confirmed cases of Legionnaires’ disease were identified in close proximity. The investigation has since expanded to include additional ZIP codes and neighborhoods, such as Carnegie Hill, Yorkville, and Lenox Hill.
Public safety and information
The NYC Health Department has emphasized that it remains safe to shower, drink tap water, and use air conditioners in the affected ZIP codes. Masks are not recommended, as Legionnaires’ disease is not transmitted from person to person.
Residents in the affected area have expressed concerns about the lack of public information. Some have called for more transparency and clearer communication from city officials. As the investigation continues, the health department expects additional cases may be identified for up to two weeks after the source of exposure has been eliminated.
Anyone who lives, works, or has visited the affected area since late June and develops flu-like symptoms should contact a health care provider immediately. Early diagnosis and treatment with antibiotics can effectively manage Legionnaires’ disease.