NEW YORK / RankWire.AI / – New York City health officials identified Legionella DNA in a Yankee Stadium cooling tower during an investigation into an outbreak in the South Bronx. As of Tuesday night, the city confirmed 11 cases of Legionnaires’ disease. One individual has died, and three patients remain 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 affected region includes parts of the Melrose and Morrisania neighborhoods. Health officials sampled cooling towers while investigating potential environmental sources of the infections. PCR testing can detect genetic material from Legionella bacteria, but it does not confirm whether the bacteria are still alive. To determine bacterial viability, culture testing is necessary, and officials noted this process can take up to two weeks.
The New York Yankees stated that the current outbreak has not been linked to Yankee Stadium. The team explained that its cooling towers were installed in 2024 and are regularly checked for water quality. A Legionella test on August 20 returned a negative result. The Yankees also performed weekly water quality and bacteriological indicator testing on August 26, September 2, and September 9, prior to city investigators collecting a sample from the stadium on September 11.
Stadium cooling tower disinfected as city expands testing efforts
All 10 cooling towers with preliminary positive PCR results have been ordered by city health officials to undergo thorough cleaning and disinfection. The New York City Health Department mandated that this work be completed by September 14. Health Commissioner Alister Martin later confirmed that each tower showing concerning results had been remediated. The Yankees stated that their stadium cooling tower was drained, cleaned, and disinfected on September 13, after the city informed them of the preliminary finding.
Legionnaires’ disease is a form of pneumonia caused by Legionella bacteria. Infection typically occurs when individuals breathe in small water droplets containing the bacteria. The disease usually does not spread from person to person. Symptoms may include fever, cough, and difficulty breathing. Officials advised anyone who has lived, worked, or visited the South Bronx area since late August to seek medical attention if flu-like symptoms develop.
Authorities continue to investigate 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 not yet provided the necessary testing data at the time of the findings’ release. Investigators are still reviewing lab results and case information from the South Bronx cluster. The ongoing inquiry includes examining cooling towers at Yankee Stadium and other nearby properties, as officials work to identify the source linked to the confirmed illnesses.
The Health Department stated that residents in ZIP codes 10451 and 10456 can continue using tap water, showers, and air conditioning normally. Officials also clarified that entering buildings associated with the 10 cooling towers does not pose an additional risk. The Yankees mentioned that health authorities have not asked them to postpone any games at Yankee Stadium. City officials remain vigilant as laboratory culture testing continues on samples collected during the South Bronx Legionnaires’ disease investigation.