Legionnaires’ Disease Cases Grow in NYC

Cooling towers on 76 buildings on New York’s City Upper East Side have tested positive for the Legionella bacteria as of July 14, the city’s Department of Health and Mental Hygiene said. Furthermore, Legionnaires’ disease has been confirmed in 63 people since the outbreak began, but no deaths have been reported.

A dozen people are now hospitalized, and 40 people have been discharged from the hospital. 

Legionnaires’ disease is a type of pneumonia caused by Legionella bacteria that grow in warm water. Legionnaires’ disease causes flu-like symptoms, and complications from the disease can be serious and even fatal, if left untreated. People who breathe in water vapor (mist) that contains Legionella bacteria can get sick.

Most people who are exposed to the bacteria do not develop Legionnaires’ disease. Illness usually occurs after high or repeated exposure, especially in people who are at increased risk.

Legionnaires’ disease is not contagious, and you cannot get Legionnaires’ disease by drinking water, cooking, or using air conditioning. The bacteria that cause Legionnaires’ disease does not spread through cooled air from air conditioners.

No vaccine or medicine can prevent Legionnaires’ disease, but it can be treated with antibiotics, and most people get better with early treatment. The best way to prevent the disease is through the proper maintenance of water systems where Legionella may grow.

In NYC, building owners are required to register cooling towers. This allows the NYC Health Department to investigate quickly when it is notified of clusters of Legionnaires’ disease cases. Building owners also need to test the water routinely in the cooling tower for the presence of Legionella and do routine checks of their system as required by NYC cooling tower regulations. They also need to test the water routinely for the presence of Legionella. You can look up results of Health Department inspections of cooling tower systems by building address or building identification number (BIN).

As CMM previously reported, every building identified to have tested positive for the presence of Legionella bacteria has been ordered to clean and disinfect its cooling tower immediately out of an abundance of caution. A positive polymerase chain reaction (PCR) test result does not confirm that a building is the source of the outbreak. PCR testing detects the presence of Legionella bacteria but cannot determine whether the bacteria are alive or dead. Only live Legionella bacteria can cause illness, NYC health officials said.