New York City health officials continue to investigate a Legionnaires’ disease outbreak on the Upper East Side that has resulted in five deaths and 82 confirmed cases, with eight patients still hospitalized.
Authorities report no new cases in the past six days, indicating that the source of exposure may have been eliminated, though the investigation remains active.
Legionnaires’ disease is a severe form of pneumonia caused by Legionella bacteria that spread through aerosolized water droplets.
Typical sources include building water systems such as cooling towers, hot tubs, plumbing networks, cruise ships and spas, and the illness is not transmitted from person to person.
Infection occurs when contaminated droplets are inhaled or when contaminated water is aspirated into the lungs, and outbreaks are almost always linked to commercial‑type building water systems.
Household systems rarely cause disease, but unclean humidifiers can become contaminated and pose a risk.
Common symptoms are cough, shortness of breath, fever, muscle aches and headache, with some patients also experiencing diarrhea, nausea or confusion.
Symptoms usually appear two to fourteen days after exposure, and effective treatment relies on prompt antibiotic therapy.
While mortality is low for healthy, younger individuals, the risk of severe illness rises for older adults, smokers and those with weakened immune systems.
Early medical evaluation and treatment are essential for anyone displaying symptoms, especially those with known risk factors.
Preventive efforts focus on regular maintenance and cleaning of cooling towers, hot tubs, plumbing systems and humidifiers to limit bacterial growth.
