Commonground
Senior Moderator
All Cooling Towers with Live Bacteria Have Already Been Cleaned and Disinfected
Anyone Who Lives In, Works In, or Recently Visited ZIP Codes 10451, 10455, 10456, or 10459 Should See a Doctor If They Develop Flu-Like Symptoms
September 23, 2026 — Today, the New York City Health Department announced that culture testing confirmed live Legionella bacteria in seven cooling towers in the South Bronx as part of the investigation into a cluster of Legionnaires’ disease in the area.
All seven cooling towers were cleaned and disinfected early last week after initial PCR screening detected Legionella in 10 cooling towers. More culture testing is underway and the list of cooling towers with positive results will be updated daily at NYC Health: Legionnaires' Disease.
“We are moving decisively and deliberately to protect New Yorkers from this Legionnaires’ disease cluster in the South Bronx. We’ve taken an aggressive response, and every cooling towers with a positive culture test so far was cleaned and disinfected more than a week ago,” said NYC Health Commissioner Dr. Alister F. Martin. “Our community health workers have been on the ground since we launched this investigation, speaking with more than 3,200 people, distributing more than 8,800 informational flyers, and reaching out to more than 280 organizations and businesses in the area. We will continue to move with urgency and keep New Yorkers informed as this investigation unfolds.”
As of September 22, the Health Department has identified 22 cases of Legionnaires’ disease associated with this cluster. 3 people are currently hospitalized, and 15 have been discharged from the hospital. Sadly, two people have died.
Out of an abundance of caution, the Health Department advises anyone who lives in, works in, or has recently visited ZIP codes 10451, 10455, 10456, or 10459 to seek medical evaluation if they develop flu-like symptoms. Symptoms of Legionnaires’ disease can appear up to 14 days after exposure.
The Health Department uses multiple testing methods to identify Legionella bacteria and to ensure the most accurate and actionable as possible. When a cooling tower receives a positive test result of any kind, the Health Department orders the building owner to clean and disinfect the tower. The Health Department’s Public Health Laboratory uses two testing method: polymerase chain reaction (PCR) screening tests and confirmatory culture testings.
PCR testing detects Legionella DNA quickly but cannot distinguish between live and dead cells. Only live Legionella bacteria can cause Legionnaires’ disease.
Culture testing involves incubating samples from cooling towers for up to two weeks to determine whether live bacteria grow. When bacteria grow, the result confirms the presence of live Legionella. Because of the time required to complete culture testing, a cooling tower is cleaned and disinfected before a positive culture result is confirmed. This means all seven cooling towers identified to date as having live bacteria have already been remediated.
Anyone Who Lives In, Works In, or Recently Visited ZIP Codes 10451, 10455, 10456, or 10459 Should See a Doctor If They Develop Flu-Like Symptoms
September 23, 2026 — Today, the New York City Health Department announced that culture testing confirmed live Legionella bacteria in seven cooling towers in the South Bronx as part of the investigation into a cluster of Legionnaires’ disease in the area.
All seven cooling towers were cleaned and disinfected early last week after initial PCR screening detected Legionella in 10 cooling towers. More culture testing is underway and the list of cooling towers with positive results will be updated daily at NYC Health: Legionnaires' Disease.
“We are moving decisively and deliberately to protect New Yorkers from this Legionnaires’ disease cluster in the South Bronx. We’ve taken an aggressive response, and every cooling towers with a positive culture test so far was cleaned and disinfected more than a week ago,” said NYC Health Commissioner Dr. Alister F. Martin. “Our community health workers have been on the ground since we launched this investigation, speaking with more than 3,200 people, distributing more than 8,800 informational flyers, and reaching out to more than 280 organizations and businesses in the area. We will continue to move with urgency and keep New Yorkers informed as this investigation unfolds.”
As of September 22, the Health Department has identified 22 cases of Legionnaires’ disease associated with this cluster. 3 people are currently hospitalized, and 15 have been discharged from the hospital. Sadly, two people have died.
Out of an abundance of caution, the Health Department advises anyone who lives in, works in, or has recently visited ZIP codes 10451, 10455, 10456, or 10459 to seek medical evaluation if they develop flu-like symptoms. Symptoms of Legionnaires’ disease can appear up to 14 days after exposure.
The Health Department uses multiple testing methods to identify Legionella bacteria and to ensure the most accurate and actionable as possible. When a cooling tower receives a positive test result of any kind, the Health Department orders the building owner to clean and disinfect the tower. The Health Department’s Public Health Laboratory uses two testing method: polymerase chain reaction (PCR) screening tests and confirmatory culture testings.
PCR testing detects Legionella DNA quickly but cannot distinguish between live and dead cells. Only live Legionella bacteria can cause Legionnaires’ disease.
Culture testing involves incubating samples from cooling towers for up to two weeks to determine whether live bacteria grow. When bacteria grow, the result confirms the presence of live Legionella. Because of the time required to complete culture testing, a cooling tower is cleaned and disinfected before a positive culture result is confirmed. This means all seven cooling towers identified to date as having live bacteria have already been remediated.