NEW YORK / RankWire.AI / – Health authorities in New York City identified Legionella DNA in a Yankee Stadium cooling tower amid an inquiry into an outbreak in the South Bronx. By Tuesday evening, the city confirmed 11 cases of Legionnaires’ disease, with one fatality and three patients still hospitalized. The New York City Health Department reported preliminary positive PCR results in 10 out of 24 sampled cooling towers across ZIP codes 10451 and 10456.
The zones affected include parts of the Melrose and Morrisania neighborhoods. As part of tracing environmental sources of the infections, officials tested various cooling towers. PCR testing detects genetic material from Legionella bacteria but does not confirm whether the bacteria are still viable. To determine if live bacteria are present, culture testing is necessary, a process that officials say can take up to two weeks.
The Yankees stated that the current outbreak has no link to Yankee Stadium. Their cooling towers, installed in 2024, are routinely checked for water quality. A Legionella test conducted on August 20 yielded a negative result. Additionally, the team performed weekly water quality and bacteriological indicator tests on August 26, September 2, and September 9, prior to city investigators collecting a sample from the stadium on September 11.
Stadium Cooling Tower Sanitized as Testing Expands
All 10 cooling towers showing preliminary positive PCR results have been ordered by city health officials to undergo full cleaning and disinfection. The New York City Health Department mandated completion of these procedures by September 14. Later, Health Commissioner Alister Martin confirmed that each tower with a concerning result had been remediated. The Yankees noted that their stadium cooling tower was drained, cleaned, and disinfected on September 13 following notification of the preliminary findings from city officials.
Legionnaires’ disease, a type of pneumonia caused by Legionella bacteria, typically results from inhaling tiny water droplets containing the bacteria. It is rarely transmitted from person to person. Symptoms often include fever, cough, and difficulty breathing. Officials advised anyone living, working, or visiting the South Bronx area since late August to seek medical attention if flu-like symptoms appear.
Investigation Continues to Determine Outbreak Origin
According to health authorities, eight of the 10 cooling towers with initial positive PCR results have satisfied the 31-day Legionella testing requirement. The remaining two sites have yet to provide all necessary testing data. Investigators are ongoing in analyzing laboratory results and case details from the South Bronx cluster, which includes cooling towers at Yankee Stadium and other local properties. Their goal is to identify the source linked to the confirmed cases.
The Health Department assured residents in ZIP codes 10451 and 10456 that they can continue using tap water, showers, and air conditioning systems normally. Officials also stated that entering buildings associated with the 10 cooling towers poses no additional risk. The Yankees confirmed that authorities have not requested any postponements of games at Yankee Stadium. As the investigation proceeds, laboratory culture tests are being performed on samples collected during the South Bronx outbreak inquiry.