NEW YORK / RankWire.AI / – Early testing has revealed Legionella DNA presence in a cooling tower located at Yankee Stadium, as authorities in New York City investigate a cluster of Legionnaires’ disease cases in the South Bronx. As of Tuesday night, the city confirmed 11 cases, including one fatality, with three individuals still hospitalized. The New York City Health Department has identified 10 cooling towers that tested positive preliminarily for Legionella via PCR across ZIP codes 10451 and 10456, which encompass parts of Melrose and Morrisania.
During the investigation, city health officials sampled 24 cooling towers. Of these, 10 yielded positive PCR results, including the tower at Yankee Stadium located at 1 E. 161st St. PCR tests are capable of detecting Legionella bacteria’s genetic material but do not determine if the bacteria are alive. Since only living Legionella bacteria can cause illness, further laboratory culture testing is currently underway to assess whether viable bacteria were present in the sampled towers.
The Yankees stated that no confirmed cases within the current cluster have been linked to Yankee Stadium. The team clarified that its cooling towers were installed in 2024 and are subject to routine water quality checks. According to the Yankees, a Legionella test conducted on August 20 returned negative, and weekly water quality and bacteriological indicator testing was performed on August 26, September 2, and September 9 before the city collected its PCR sample on September 11.
Post-positive test cleaning protocols for cooling towers
Following the detection of positive PCR results, the New York City Health Department mandated comprehensive cleaning and disinfection for all 10 towers. The deadline set for remediation was September 14. Health Commissioner Alister Martin announced on Tuesday that all towers with concerning results had been properly cleaned and disinfected. After the city notified the Yankees of its preliminary findings, the cooling tower at Yankee Stadium was drained, cleaned, and disinfected on September 13, according to the team.
Legionnaires’ disease is a form of pneumonia caused by Legionella bacteria. Infection typically occurs through inhalation of tiny water droplets containing the bacteria, and it generally does not transmit from person to person. Symptoms may include fever, cough, and breathing difficulties. City officials have urged individuals who have lived, worked, or visited the South Bronx area since late August to seek medical advice if flu-like symptoms develop.
Ongoing investigation into Legionnaires’ outbreak in South Bronx
According to health officials, eight of the 10 towers with initial positive results have fulfilled the city’s 31-day Legionella testing requirement, while two sites had not yet supplied all necessary testing data at the time of the announcement. The investigation continues to focus on cooling towers in the affected South Bronx neighborhoods, including sites at Yankee Stadium as well as other properties. Authorities are still employing laboratory testing and epidemiological analysis to identify the exposure source linked to the confirmed cases.
The Health Department reassured residents in ZIP codes 10451 and 10456 that it is safe to continue drinking tap water, take showers, and operate air conditioning units unless official guidance states otherwise. It also emphasized that being inside buildings connected to these cooling towers does not elevate risk. The Yankees confirmed that city health officials have not requested postponement of any games at Yankee Stadium. Officials continue to monitor the cases as laboratory results from samples collected during the South Bronx investigation are analyzed.