Bronx Legionnaires' disease outbreak prompts NYC health officials to order the cleaning of 10 cooling towers

The New York City Department of Health is taking new action against a deadly Legionnaires' disease cluster in the Bronx.

Health officials on Sunday ordered 10 cooling towers that tested positive for Legionella bacteria to be cleaned and disinfected. They are located in the zip codes of 10451 and 10456, and include Yankee Stadium.

The cooling towers with positive PCR results are located at:

• 820 Concourse Village West
• 234 E. 149th St.
• 1 E. 161st St.
• 470 E. 161st St.
• 1265 Franklin Ave.
• 567 Melrose Ave.
• 3339 Park Ave.
• 1160 Teller Ave.
• 890 Washington Ave.
• 1085 Washington Ave.

At a town hall addressing community concerns, officials said preliminary testing ordered just a few days ago found that traces of the bacteria were detected in those cooling towers.

An investigation was launched late last week as officials continue to try to determine the source of this new outbreak, which is concentrated in the Melrose and Morrisania sections of the borough. This latest community cluster has already led to one death and a total of nine cases. Three people are still hospitalized. 

Yankee Stadium addresses Bronx Legionnaires cluster

In addition to Yankee Stadium as a site with a cooling tower of concern, other towers cited by the health department are located at Boricua College's Bronx campus and a Morrisania dialysis center.

Yankee Stadium released the following statement, which says, in part:

"In 2024, the Yankees installed new, state-of-the-art, high-efficiency chiller towers at Yankee Stadium, which have undergone water quality and bacteriological indicator testing on a weekly basis over the last three years.

"In accordance with New York City Department of Health regulations, Yankee Stadium provides these results to the NYC DOH on a monthly basis. In the most recent monthly testing on Aug. 20, which was provided to the Department of Health, results were negative for Legionella bacteria. Subsequent to that test, weekly water quality and bacteriological indicator testing was performed on Aug. 26, Sept. 2 and Sept. 9.

"Due to the recent community cluster of Legionella bacteria in the Melrose and Morrisania areas of the Bronx (zip codes 10451 and 10456) last week, the NYC Dept. of Health conducted 24 PCR (Polymerase Chain Reaction) tests of cooling towers in the area, including one at Yankee Stadium on Sept. 11. Yankee Stadium tested positive for trace amounts of Legionella bacteria and was one of 10 cooling towers in the Bronx that tested positive.

"A PCR test, which is different from the independent monthly testing Yankee Stadium regularly undertakes, can detect the presence of Legionella bacteria DNA but cannot determine whether the bacteria are alive or dead and does not confirm that a cooling tower is the source of exposure. Only live Legionella bacteria can cause illness.

"No current cases have been associated with Yankee Stadium. Additionally, the New York City Department of Health has not at any point this month asked us to postpone our games.

City health officials said they are determined to identify the source of the Bronx cluster in an effort to prevent more illness.

"Folks better believe if we find that a building owner was noncompliant, didn't do what they're supposed to do, dropped the ball, there will be consequences and we will hold them accountable," city Health Commissioner Dr. Alister Martin said.

All 10 cooling towers in the two impacted zip codes are required to complete remediation by Monday.

For anyone who wants to talk to the city health department in person, there is an in-person town hall scheduled for Tuesday at 6 p.m. at Metropolitan College in the Bronx. 

What to know about Legionnaires' disease

Legionnaires' disease, which is spread by breathing in mist containing Legionella bacteria, is not contagious. However, its symptoms, which can appear two to 14 days after exposure, can get serious if left unchecked.

"If you have things like cough, fever, shortness of breath, that is a sign to go see a doctor," Martin said. "Being over the age of 50 or having underlying medical conditions, such as lung disease, also people who smoke and vape who are at increased risk."

Other symptoms include muscle aches, headaches, fatugue, confusion, and gastrointestinal issues.

According to the American Lung Association, Legionella bacteria grow in warm, fresh water, such as cooling towers, hot tubs, large plumbing systems, and decorative fountains.

Editor's note 9/14/26: This article has been updated to clarify the scope of the Legionnaire's investigation.