First death reported in NYC’s legionnaires disease outbreak as number of infected rises

First death reported in NYC’s legionnaires disease outbreak as number of infected rises

A Legionnaires' disease outbreak centered on Manhattan's Upper East Side has claimed its first life, health officials announced Friday. The death comes as the number of infected individuals continues to climb, with the city reporting 67 cases as of 9 p.m. Thursday night.

New York City Health Commissioner Dr. Alister F. Martin confirmed the fatality in a statement.

"I am saddened to report that one person has died in connection with the Legionnaires’ disease community cluster on the Upper East Side,"

Dr. Alister F. Martin, NYC Health Commissioner

Officials declined to provide the age, identity, or specific medical details regarding the deceased out of respect for personal privacy. Currently, 12 people remain hospitalized in connection with the cluster.

Tracking the Outbreak

City officials began tracking the outbreak on July 2, after two unrelated cases were diagnosed in the area. The infection count rose steadily through the month: reaching 10 patients initially, then 14 by July 4, and climbing to 18 shortly thereafter. By the end of the first week, cases reached 23, with 17 hospitalizations.

The numbers continued to accelerate, hitting 28 cases and later 36 within six days of the start of the outbreak. By the time the count reached 54, 56, and 59 patients, officials had not yet reported any deaths. The total reached 60 patients less than two weeks after the first case was diagnosed.

The Health Department has focused its investigation on specific Upper East Side zip codes, including 10075, 10028, and 10128, as well as the eastern portion of Central Park between East 75th and 97th Streets. Residents or visitors to these areas who experience flu-like symptoms, nausea, diarrhea, or confusion are urged to seek medical care immediately, as symptoms typically begin within two days to two weeks after exposure.

The Search for the Source

Investigators are scrutinizing air conditioning systems and rooftop cooling towers, which can release water vapor carrying Legionella bacteria. The NYC Health Department has repeatedly stated that the source is rooftop cooling towers rather than building plumbing. Officials noted that drinking water, bathing, and cooking water remain safe, and that air conditioning units themselves pose no danger.

Testing has identified either living or dead Legionella bacteria in cooling towers on 76 buildings across the Upper East Side and one on the Upper West Side. These buildings include private schools, pricey apartment houses, and prominent museums. One specific site, 1511 Third Avenue at the corner of East 85th Street in Yorkville, was the first publicly identified building with a positive test and was ordered to be cleaned.

The city has ordered all affected buildings to drain, clean, and disinfect their cooling towers. While 31 towers were previously confirmed as disinfected, later tests revealed an additional 44 contaminated towers, bringing the total of positive sites to 75 in the Upper East Side alone. One unregistered cooling tower that tested negative was also ordered to be cleaned.

Medical Context and Risks

Legionnaires' disease is a form of pneumonia caused by Legionella bacteria, which thrive in warm water and can spread via hot tubs, showerheads, and cooling towers. People typically contract the illness by inhaling tiny droplets of contaminated water. The disease is not spread person-to-person.

According to the U.S. Centers for Disease Control and Prevention (CDC), the disease is treatable with antibiotics if caught early, but it kills about 10% of patients. The CDC further notes that adults with certain chronic health conditions face a higher risk of complications.

This is not the first such event in the city. Last year, an outbreak in the Harlem neighborhood sickened more than 100 people and resulted in seven deaths.

The city continues to monitor the situation, and Mayor Zohran Mamdani previously announced that the Health Department would release a list of all Legionella-positive cooling tower addresses, though a specific date for that release has not been provided.