Pedestrians walk by water coming out of an open fire hydrant in the Harlem section of Manhattan as excessive heat and high temperatures continues in New York City on Thursday, July 17, 2025. City officials said Monday that a fifth person has died from Harlem’s Legionnaires’ disease outbreak. Photo by John Angelillo/UPI | License Photo
A fifth person has died amid Central Harlem’s legionnaires’ disease outbreak, New York City health officials said, as they continue to investigate the cluster.
Dr. Michelle Morse, acting health commissioner for New York City, announced the death in a brief statement to X on Monday night, saying that health officials have concluded that an unidentified individual who died before mid-August from the disease is connected to the Harlem outbreak.
The cluster was first detected in Central Harlem on July 25, and has since grown to 108 confirmed cases as of Tuesday. Fourteen patients have been hospitalized.
Officials said the cluster has been identified in the ZIP codes of 10027, 10030, 10035, 10037 and 10039, but stated the risk to residents of those communities remains low.
Legionnaires’ disease is a type of pneumonia caused by Legionella bacteria that grow in warm water. Those who inhale mist that contains the bacteria can get sick with the disease, which can cause flu-like symptoms, while complications can be fatal. People usually develop symptoms between two and 10 days after exposure.
According to the U.S. Centers for Disease Control and Prevention, between 8,000 and 18,000 people are hospitalized with Legionnaires’ disease each year in the United States.
New York City health officials said the first confirmed case occurred on July 22 and climbed to a high of 11 newly diagnosed cases on Aug. 2, since thne there have been a drop in new cases. The last two cases were diagnosed on Aug. 12, according to the city’s data.
“Based on epidemiological evidence, remediation efforts have been effective as new cases continue to decrease,” Morse said in a statement.
“The health department is continuing our investigation.”
Health officials said they have sampled and tested water from cooling towers in the investigation zone. Though the city did not say how many tested positive for the disease, it said those with initial positive results for legionella bacteria “have completed the treatment required by the health department.”
“We are continuing to monitor and let buildings know if additional treatment is needed,” the city’s health department said.
