The Legionnaires' disease cluster in the South Bronx has grown to 12 cases, according to the New York City Health Department, up from nine as of Sept. 12. The department's latest count, posted Sept. 15 at 9:50 p.m., lists two people currently hospitalized, eight discharged, one who did not need hospital care, and one death.
The newest total came after the city's Sept. 14 deadline for owners of 10 cooling towers in ZIP codes 10451 and 10456 to clean and disinfect them. For families in Melrose and Morrisania, that timing raises an understandable worry: if the towers were cleaned, why are more people still being diagnosed?
The answer lies in how the illness develops, and it affects how long residents should keep paying attention to a cough or fever. Health officials have not identified the source of the cluster, and the lab results that could help narrow it down are still pending.
Developing Story Note: This report covers new developments involving the Legionnaires' disease cluster in Melrose and Morrisania. Information may change as authorities, researchers, hospitals, courts, or public health agencies release additional findings. Case figures come from the NYC Health Department page last updated Sept. 15, 2026, at 9:50 p.m.
Twelve Cases and Fewer Patients Still Hospitalized
As of Sept. 12, the city counted nine cases, according to the Health Department release ordering the cleanings. At that point, three people were hospitalized, four had been discharged, one had not needed hospital care, and one had died. The newest count adds three cases and also shows more patients recovering, with discharges doubling to eight.
MedicalDaily previously reported on the city's order to clean 10 South Bronx cooling towers after preliminary screening detected Legionella, including at Yankee Stadium. Since then, the cleaning deadline has passed, the city has held virtual and in-person town halls, and the official case count has grown by a third. The central unknown has not changed, because no tower has been confirmed as the source.
Developing Story Timeline
Sept. 15, 2026, 9:50 p.m.: The Health Department reported 12 cases. Two patients were hospitalized, eight had been discharged, one did not need hospital care, and one had died.
Sept. 15, 2026: The Health Department held an in-person town hall at Metropolitan College in the Bronx.
Sept. 13, 2026: The city announced that 10 cooling towers had been ordered cleaned and disinfected by Sept. 14 and held a virtual town hall. It reported nine cases as of Sept. 12.
Sept. 10, 2026: The Health Department opened its investigation with five confirmed cases. One person had already died.
Cleaning Came First, Culture Results Come Later
The Health Department sampled 24 cooling towers for the investigation. The 10 flagged towers tested positive on a PCR test, which detects Legionella DNA but cannot tell whether the bacteria are alive or dead. A more conclusive culture test is being run on every sampled tower and can take up to two weeks. Only live bacteria cause illness, so culture results are needed to show which towers had growing Legionella when the water was collected.
That is why a positive PCR screen does not identify a source. The department also notes that even a culture-positive tower may or may not be the source of exposure. During the Upper East Side cluster earlier this summer, which reached 94 cases and 11 deaths as of Aug. 28, the department likewise ordered PCR-positive towers cleaned before culture results were in.
To reduce the risk of ongoing exposure while culture testing continues, the city required every PCR-positive tower to be drained, cleaned, and disinfected. The Yankees told NY1 that the stadium's tower was drained, cleaned, and disinfected on the morning of Sept. 13 and that no current cases have been associated with the stadium. Another flagged tower is at 234 E. 149th St., the address of NYC Health + Hospitals/Lincoln. The city says there is no added risk from being inside any of the 10 buildings.
Melrose and Morrisania Households Weighing Every Cough
Symptoms typically develop two to 14 days after exposure, according to the Health Department. Someone who breathed contaminated mist before a tower was cleaned could still become sick days later, and testing and confirmation add more time before a case is counted. New diagnoses this week do not, by themselves, show that exposure is continuing.
By that math, a person exposed shortly before the Sept. 14 cleaning deadline could develop symptoms through about Sept. 28, although the department has not said when it will consider the exposure period over. Anyone who lives or works in the area, or has visited since late August, and develops flu-like symptoms such as fever, cough, or difficulty breathing should contact a health care provider right away and mention possible Legionnaires' disease.
"Most important thing to know is to continue to monitor yourself for symptoms," Health Commissioner Dr. Alister Martin said on Sept. 13, the day of the department's virtual town hall, according to NY1. "If you have things like cough, fever, shortness of breath, that is a sign to go see a doctor and to not delay."
Risk is concentrated in certain groups. Adults 50 and older, people who smoke or vape, and people with chronic heart, lung, kidney, or liver disease, diabetes, or weakened immune systems face higher risk. Headache, fatigue, loss of appetite, confusion, and diarrhea can also occur, so caregivers of older relatives in the two ZIP codes may want to check in often.
Help finding a provider is available through 311 or 844-NYC-4NYC, regardless of immigration or insurance status. The department, which has posted a resident notice in English, Spanish, French, and Haitian Creole, says it is safe to shower, drink tap water, and use air conditioners in the affected area. Mist from a cooling tower disperses outdoors and does not affect indoor air conditioning, window units, or building plumbing, according to the department. Legionnaires' disease also does not spread from person to person.
Town Hall Frustration and the Questions Still Open
At the Sept. 15 town hall at Metropolitan College, some residents questioned the timing of the city's response. "It's after the fact, and that's when they want to do something," resident Roberta Yancey told News 12.
Several questions remain. Culture results are pending, the source is unconfirmed, and more cases could still be identified within the incubation window. The department says it will inspect any tower that tests positive to review its compliance with city rules, and it has said two of the 10 flagged towers, at 820 Concourse Village West and 1265 Franklin Ave., had not provided required testing information. The city has not publicly announced penalties tied to this cluster.
MedicalDaily will track the culture results and any change in the case count. Until officials report otherwise, the most useful step for households is to watch for symptoms and seek same-day care if they appear.
Key Questions Answered
How many cases are linked to the South Bronx cluster?
The Health Department reported 12 cases as of Sept. 15 at 9:50 p.m. Two people were hospitalized, eight had been discharged, one did not need hospital care, and one had died.
Why are cases still being reported after the towers were cleaned?
Symptoms typically develop two to 14 days after exposure, and confirming a diagnosis takes additional time. People exposed before the cleaning can still become ill afterward.
Has the source of the cluster been found?
No source has been confirmed. Culture tests on the sampled towers can take up to two weeks and will show which towers had live bacteria when they were sampled.
Is it safe to drink tap water or use air conditioning?
Yes, according to the Health Department, which also says it is safe to shower. Legionnaires' disease is not contagious and does not spread from person to person.
Who should seek medical care?
Anyone who lives or works in the affected ZIP codes, or has visited since late August, and develops flu-like symptoms should contact a provider immediately. People 50 and older, people who smoke or vape, and those with certain chronic conditions face higher risk.
Is Yankee Stadium safe to visit?
The city says there is no additional risk from being inside any of the flagged buildings. The Yankees said the stadium tower was cleaned on Sept. 13 and that no current cases have been associated with the stadium.
