NEW YORK / RankWire.AI / – Initial tests have found Legionella DNA in a cooling tower located at Yankee Stadium amid an ongoing investigation into a Legionnaires’ disease cluster in the South Bronx. By Tuesday night, New York City authorities confirmed 11 cases, including one fatality, with three individuals still hospitalized. The New York City Health Department pinpointed 10 cooling towers testing positive via preliminary PCR results across ZIP codes 10451 and 10456, covering parts of Melrose and Morrisania.

In the course of examining the cluster, city health officials sampled a total of 24 cooling towers. Among these, 10 returned positive PCR results, including the one at Yankee Stadium located at 1 E. 161st St. PCR testing identifies Legionella bacteria’s genetic material but does not determine whether the bacteria are alive. As only living Legionella bacteria pose a health threat, additional laboratory culture testing is being conducted to verify if viable bacteria were present in these sampled towers.
The Yankees have stated that none of the cases linked to the current cluster have been associated with Yankee Stadium. The team confirmed its cooling towers, installed in 2024, are subject to routine water quality assessments. According to the Yankees, a Legionella test conducted on Aug. 20 yielded a negative result. The team also performed weekly water quality and bacteriological indicator tests on Aug. 26, Sept. 2, and Sept. 9 before the city collected its PCR sample on Sept. 11.
Cooling systems undergo cleaning following initial positive results
All 10 cooling towers with preliminary positive PCR findings have been ordered by the New York City Health Department to undergo thorough cleaning and disinfection. The city mandated that this remediation be completed by Sept. 14. Health Commissioner Alister Martin reported on Tuesday that all towers with concerning results had been disinfected. The Yankees explained that the cooling tower at Yankee Stadium was drained, cleaned, and disinfected on Sept. 13 after the city notified the team of its preliminary PCR result.
Legionnaires’ disease, a form of pneumonia caused by Legionella bacteria, results mainly from inhaling tiny water droplets containing the bacteria. Typically, person-to-person transmission does not occur. Symptoms can include fever, cough, and breathing difficulties. City officials advised individuals who have lived, worked, or visited the South Bronx area since late August to seek medical attention if they develop flu-like symptoms.
Ongoing investigation into South Bronx Legionnaires’ cases continues
According to health authorities, eight of the 10 towers with positive initial results met the city’s 31-day Legionella testing requirement. Two sites had yet to provide the necessary testing documentation at the time of the announcement. The investigation encompasses cooling towers across the impacted neighborhoods in the South Bronx, including sites at Yankee Stadium and other locations. Officials are still analyzing laboratory results and epidemiological data to determine the source of exposure linked to the confirmed illnesses.
The Health Department assured residents in ZIP codes 10451 and 10456 that drinking tap water, showering, and using air conditioning remain safe unless otherwise instructed. They also clarified that being inside buildings connected to these cooling towers does not pose an additional risk. The Yankees confirmed that city health officials have not requested the team to delay upcoming games at Yankee Stadium. Monitoring of confirmed cases continues as laboratory testing on samples from the South Bronx investigation progresses.