Two stricken with Legionnaires Disease on Upper East Side, cluster investigated: NYC health officials

July 4, 2026 - 04:20

New York City health officials are investigating a cluster of Legionnaires disease after two people fell ill in the Upper East Side. The patients live in the Yorkville and Carnegie Hill neighborhoods, specifically within the 10028 and 10128 zip codes, according to city officials. Both individuals are receiving medical care, and authorities are working to identify the source of the bacteria.

Legionnaires disease is a serious form of pneumonia caused by the Legionella bacteria. It is typically contracted by inhaling water vapor contaminated with the germ, often from cooling towers, hot tubs, large plumbing systems, or decorative fountains. The disease is not spread from person to person. Symptoms can include cough, shortness of breath, fever, muscle aches, and headaches, and it poses a higher risk to older adults, smokers, and people with weakened immune systems.

The New York City Department of Health and Mental Hygiene has deployed teams to test water sources in the affected area. They are focusing on cooling towers and building water systems, which are common breeding grounds for the bacteria. Residents in the Upper East Side are being urged to see a doctor if they develop flu-like symptoms, especially if they have underlying health conditions. Health officials have not yet confirmed a specific source and continue to collect samples for laboratory analysis. The investigation remains active as they try to prevent additional cases.