The NYC Health Department is actively responding to a cluster of individuals with Legionnaires’ disease in parts of Melrose and Morrisania in the South Bronx (impacted ZIP codes: 10451 and 10456), which, as of September 10, 2026, includes 5 confirmed cases, one death, and additional suspected cases that are pending confirmation.
Legionnaires’ disease (Legionellosis) is a bacterial disease which may cause pneumonia. Between 200 and 800 cases are reported each year in New York State, including New York City.
Legionnaires’ disease can be a mild respiratory illness or it can be severe enough to cause death.
Legionella bacteria exist naturally in water and moist soil. They have been found in creeks and ponds, hot and cold water taps, hot water tanks, hot tubs, water in air conditioning cooling towers and evaporative condensers, and soil at excavation sites.
The disease appears to be spread through the air from a soil or water source. All studies to date have shown that person-to-person spread does not occur.
Most healthy individuals do not become infected with Legionella bacteria after exposure. People at higher risk of getting sick are those 50 years of age or older, current or former smokers, those with a chronic lung disease (like COPD or emphysema), those with a weak immune system from diseases like cancer, diabetes, or kidney failure, and people who take drugs that suppress (weaken) the immune system (like after a transplant operation or chemotherapy).