New York City health officials are investigating a growing cluster of Legionnaires’ disease cases on the Upper East Side, a situation that has now reached the iconic Solomon R. Guggenheim Museum. As of July 10, 2026, at least 54 cases have been linked to the area, with 18 individuals remaining hospitalized. While the investigation continues, the city has identified 31 buildings where Legionella bacteria were detected in cooling towers, prompting immediate cleaning and disinfection orders for those sites.
Legionnaires’ disease is a serious form of pneumonia caused by inhaling fine water droplets containing Legionella bacteria. It is not contagious through person-to-person contact. Cooling towers, which are common components of large building air-conditioning systems, can harbor the bacteria if not properly maintained. The city’s health department emphasized that a positive test result does not definitively prove a specific building is the source of the outbreak, as current testing methods cannot always distinguish between live and dead bacteria.
The Guggenheim Museum, along with other affected locations including residential buildings and a summer day camp, has complied with the city’s directive to remediate its cooling tower. Museum officials stated that the building remains safe for visitors and employees, noting that they conduct regular, independent testing and maintenance of their cooling systems. The museum has not been closed, and health authorities have advised that no changes to daily routines are necessary for the public.
As the investigation proceeds, the city is working to pinpoint the exact source of the contamination. Nineteen of the 31 identified buildings have already completed the required disinfection process, with the remainder expected to finish by the end of the weekend. No deaths have been reported in this current cluster, and health officials continue to monitor the situation closely to prevent further spread.