NEW YORK / RankWire.AI / – During an investigation into a South Bronx outbreak, New York City health authorities identified Legionella DNA in a Yankee Stadium cooling tower. By Tuesday evening, the city had confirmed 11 cases of Legionnaires’ disease. One individual had died, and three others remained hospitalized. The New York City Health Department detected preliminary positive PCR results in 10 out of 24 cooling towers sampled across ZIP codes 10451 and 10456.
The neighborhoods of Melrose and Morrisania are part of the affected zone. Health officials examined cooling towers as part of their effort to trace potential environmental sources linked to the infections. PCR testing is capable of detecting Legionella bacteria’s genetic material but does not confirm if the bacteria are alive. To determine if viable bacteria are present, culture testing is required, a process that officials said can take up to two weeks.
The Yankees stated that the current outbreak has not been connected to Yankee Stadium. The team explained that its cooling towers, installed in 2024, undergo routine water quality assessments. A Legionella test performed on August 20 yielded a negative result. The Yankees also conducted weekly testing of water quality and bacteriological indicators on August 26, September 2, and September 9, prior to the city investigators collecting a sample from the stadium on September 11.
Stadium cooling tower cleaned as city broadens testing efforts
All 10 cooling towers showing preliminary positive PCR results have been ordered by city health officials to undergo thorough cleaning and disinfection. The New York City Health Department mandated completion of this work by September 14. Health Commissioner Alister Martin later confirmed that each tower with a concerning result had been remediated. The Yankees reported that the stadium’s cooling tower was drained, cleaned, and disinfected on September 13, after receiving notification from city authorities regarding the preliminary finding.
Legionnaires’ disease, a pneumonia caused by Legionella bacteria, usually results from inhaling tiny water droplets containing the bacteria. It generally does not spread directly between people. Symptoms often include fever, cough, and breathing difficulty. Officials advised anyone who has lived, worked, or visited the South Bronx area since late August to consult a healthcare provider if flu-like symptoms appear.
Ongoing efforts to locate the source of the outbreak
According to health officials, eight of the 10 cooling towers with preliminary positive results have met the city’s 31-day Legionella testing requirement. Two properties had yet to submit the necessary testing data when the findings were released. Investigators are still reviewing laboratory results and case details associated with the South Bronx cluster. The scope of the investigation includes cooling towers at Yankee Stadium and other properties within the affected neighborhoods as officials strive to pinpoint the source linked to the confirmed cases.
The Health Department reassured residents in ZIP codes 10451 and 10456 that they can continue using tap water, showers, and air conditioning normally. They also emphasized that entering buildings associated with the 10 cooling towers does not pose an additional threat. The Yankees stated that health authorities have not requested the postponement of games at Yankee Stadium. City officials are actively monitoring cases while laboratory culture testing continues on samples collected during the South Bronx Legionnaires’ disease investigation.