NEW YORK / RankWire.AI / – New York City health authorities identified Legionella DNA in a Yankee Stadium cooling tower amid an investigation into a South Bronx outbreak. The city confirmed 11 cases of Legionnaires’ disease by Tuesday night, with one fatality and three patients still hospitalized. The New York City Health Department detected preliminary positive PCR results in 10 out of 24 sampled cooling towers across ZIP codes 10451 and 10456.

The impacted areas cover sections of Melrose and Morrisania neighborhoods. As part of tracing potential environmental sources of the infections, health officials tested cooling towers. PCR testing identifies genetic material from Legionella bacteria but does not confirm if the bacteria are alive. Culturing tests, which determine whether viable bacteria are present, can take up to two weeks, according to officials.
The Yankees clarified that the current outbreak has not been associated with Yankee Stadium. They stated that their cooling towers, installed in 2024, undergo regular water quality assessments. A Legionella test on Aug. 20 returned negative. Additionally, the team conducted weekly water quality and bacteriological indicator tests on Aug. 26, Sept. 2, and Sept. 9, prior to city investigators sampling the stadium on Sept. 11.
Stadium tower disinfected as city expands testing efforts
All 10 cooling towers with preliminary positive PCR results were ordered by city health officials to be fully cleaned and disinfected. The New York City Health Department mandated completion by Sept. 14. Later, Health Commissioner Alister Martin confirmed that remediation had been carried out on each tower flagged with concerning results. The Yankees announced that their stadium cooling tower was drained, cleaned, and disinfected on Sept. 13 after being notified about the preliminary positive finding by city officials.
Legionnaires’ disease is a bacterial pneumonia caused by Legionella bacteria. Typically, infection occurs when individuals 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. Health authorities advised anyone living, working, or visiting the South Bronx area since late August to seek medical attention if flu-like symptoms develop.
Investigation continues to identify outbreak origins
According to health officials, eight of the 10 cooling towers with preliminary positive PCR results have satisfied the city’s 31-day Legionella testing requirement. The remaining two sites had yet to submit the necessary testing data at the time of the report. Authorities continue to analyze laboratory results and case information from the South Bronx cluster. The investigation encompasses cooling towers at Yankee Stadium as well as other properties within the affected neighborhoods, as officials seek the source linked to the confirmed cases.
The Health Department reassured residents of ZIP codes 10451 and 10456 that they can safely continue using tap water, showers, and air conditioning. Officials also stated that entering buildings associated with the 10 cooling towers does not pose an additional risk. The Yankees noted that health authorities have not requested the team to delay any games at Yankee Stadium. The city continues to monitor cases while lab culture tests are underway on samples collected during the South Bronx Legionnaires’ disease investigation.
