A second person has died of Legionnaires’ disease after the recent outbreak on the Upper East Side of Manhattan, the city’s health department announced Sunday.
The health department identified a cluster of Legionnaires’ disease, a lung infection caused by inhaling water droplets containing the Legionella bacterium, in Carnegie Hill and Yorkville earlier this month. The first two cases in this cluster were reported on July 2 and as of Saturday, 72 people had been diagnosed. The first death was reported on Friday.
Many cases of the disease are traced to buildings with large cooling systems, hot water tanks, water fountains and hot tubs. Symptoms include headaches, muscle aches, fever, nausea, coughing and chest pain, according to the Mayo Clinic in Minnesota. It is not contagious and can be treated with antibiotics, but in older people or those with compromised immunity, it can be serious or fatal, experts say.
In the past two weeks 183 cooling towers were inspected and tested for the Legionella bacterium, and 76 towers that had initial positive results were cleaned and disinfected, following the department’s orders. In the past, disinfection was required only after a culture came back positive, but that takes several weeks, during which time more people could be exposed.
The number of new cases in New York City has slowed, the health agency said, to fewer than one case a day in the past week, from an average of eight per day earlier this month.
The agency said fewer diagnoses suggested the source of the outbreak had been addressed.
“Our aggressive strategy of testing, enforcement, and remediation appears to have stopped the source of exposure,” health commission Alister Martin said in a statement.
Of the 72 people who were diagnosed, 50 have been released from the hospital while some are still being treated.
The announcement said the agency continues to monitor towers that tested positive.
The health department said it has also stepped up routine inspections of cooling towers in the first six months of this year, after Mayor Zohran Mamdani took office, increasing checks by 35% over the same period in 2025.