NEW YORK / RankWire.AI / – Initial analysis identified Legionella DNA in a cooling tower at Yankee Stadium as New York City investigates a Legionnaires’ disease cluster in the South Bronx. By Tuesday night, the city had confirmed 11 cases, including one fatality, with three individuals still hospitalized. The New York City Health Department identified 10 cooling towers showing positive preliminary PCR results across ZIP codes 10451 and 10456, covering parts of Melrose and Morrisania.
During their investigation, city health officials sampled 24 cooling towers, with 10 returning positive PCR results, including the tower at Yankee Stadium at 1 E. 161st St. PCR tests detect Legionella bacteria’s genetic material but cannot confirm whether the bacteria are alive. Since only live Legionella can cause illness, additional laboratory culture testing is ongoing to determine if viable bacteria were present in the sampled towers.
The Yankees stated that no confirmed cases linked to the current cluster have been connected to Yankee Stadium. The team explained its cooling towers were installed in 2024 and are regularly tested for water quality. A Legionella test on Aug. 20 yielded a negative result, and weekly water quality and bacteriological indicator tests were also performed on Aug. 26, Sept. 2, and Sept. 9, prior to the city collecting its PCR sample on Sept. 11.
Cooling towers disinfected following initial positive results
The New York City Health Department mandated thorough cleaning and disinfection of all 10 cooling towers with positive PCR outcomes, with remediation required to be completed by Sept. 14. Health Commissioner Alister Martin confirmed Tuesday that all towers with concerning positive results had been cleaned and disinfected. The Yankees reported that the Yankee Stadium cooling tower was drained, cleaned, and disinfected on Sept. 13 after the city notified the team of its preliminary finding.
Legionnaires’ disease is a form of pneumonia caused by Legionella bacteria, typically transmitted when people breathe in tiny water droplets containing the bacteria. It usually does not spread from person to person. Symptoms often include fever, cough, and breathing difficulties. City officials advised residents who have lived, worked, or visited the South Bronx area since late August to seek medical advice if they develop flu-like symptoms.
South Bronx Legionella investigation ongoing
Eight of the 10 towers with positive preliminary results complied with the city’s 31-day Legionella testing requirement, while two locations had yet to submit the necessary testing data when the findings were announced. The investigation focuses on cooling towers in the affected South Bronx neighborhoods, including sites at Yankee Stadium and other properties. Authorities continue to analyze laboratory results and epidemiological data to identify the source of exposure linked to the confirmed illnesses.
The Health Department assured residents in ZIP codes 10451 and 10456 that they can continue drinking tap water, showering, and using air conditioning unless official guidance states otherwise. They also noted that being inside buildings connected to the 10 cooling towers does not increase risk. The Yankees mentioned that city health officials have not asked the team to postpone games at Yankee Stadium. The department continues to monitor confirmed cases while laboratory testing proceeds on samples collected during the South Bronx investigation.