At the time of this writing, a deadly outbreak of Legionnaires’ Disease on the Upper East Side of New York City has more than 82 confirmed cases, with 64 of those afflicted requiring hospitalization (only eight of which are currently hospitalized). There have been five confirmed deaths.

The latest outbreak is being investigated as a “community cluster” affecting the Upper East Side neighborhoods of Carnegie Hill and Yorkville. The outbreak was first reported July 2.

The New York City official government site, www.nyc.gov, advises that any New Yorkers in ZIP codes 10028, 10128, and 10075 can continue to drink tap water, bathe, shower, cook, and use air conditioners at home, as the source of the aerosolized bacteria is cooling towers, not plumbing systems.

New Yorkers who currently live or work in the affected area, or people who have visited the area since late June and are experiencing flu-like symptoms, such as cough, fever, or difficulty breathing should contact a health care provider immediately.

Testing and Remediation

While The Ardsley, a residential co-op building on Central Park West—where one-bedroom apartments sell for nearly $1 million—had its hot water system test positive for the Legionella bacterium, a statement from the mayor’s office has dismissed it as the source of the outbreak. The building has no cooling tower, and has since disinfected its water system.

The bacteria that cause Legionnaires, Legionella pneumophila, are common, widespread, and can survive in most water systems. Eradication is not possible, only mitigation, prevention and control. A similar outbreak in the Bronx neighborhood back in 2015 sickened 130, killing 10.