New York City Health Department Updates On Community Cluster of Legionnaires' Disease

The Situation Report | August 18, 2025

The New York City Health Department provided an update on an investigation into a community cluster of Legionnaires’ disease in Central Harlem (ZIP codes 10027, 10030, 10035 and 10037) and bordering communities. One-hundred and one people have been diagnosed with Legionnaires’ disease since July 25, 2025. Four people have died, and 15 people are currently hospitalized.

The NYC Health Department has confirmed that 12 cooling towers have tested culture positive in 10 buildings for live Legionella bacteria.  Eleven of the 12 cooling towers have completed remediation. 

New Yorkers who live or work in one of the identified ZIP codes in Central Harlem with flu-like symptoms, cough, fever, or difficulty breathing should seek medical attention immediately. It is especially important for people at higher risk – including those ages 50 and older, cigarette smokers, and people with chronic lung disease or compromised immune systems – to get care if they have symptoms. Legionnaires’ disease is not contagious and can be treated with antibiotics when caught early.

Legionnaires’ disease is a type of pneumonia that is caused by the bacteria Legionella, which grows in warm water. Symptoms resemble other types of pneumonia and can include fever, chills, muscle aches, and cough. Most cases of Legionnaires’ disease can be traced to plumbing systems where conditions are favorable for Legionella growth, such as cooling towers, whirlpool spas, hot tubs, humidifiers, hot water tanks, and evaporative condensers of large air-conditioning systems.

Individuals only get sick by breathing in water vapor containing Legionella bacteria, and the disease is not transmitted from person to person. Individuals at higher risk include those 50 years old and older, cigarette smokers, and people with chronic lung disease or compromised immune systems. People living or working in the area who are experiencing these symptoms should seek medical attention with a primary care provider or seek urgent care.

HCANYS will apprise you of any further clusters and outbreaks.