Death Toll in NYC Legionnaires’ Disease Outbreak Jumps to 7: Should You Be Concerned?

Legionnaires’ disease has sickened 81 people in the New York City borough of the Bronx within the last month, and the numbers are steadily rising. (Photo: Getty Images/CDCP)

An outbreak of Legionnaires’ disease in New York City has left 81 people sick, with seven of those cases resulting in death, the office of New York City Mayor Bill de Blasio announced late Monday.

The outbreak began in mid-July in the South Bronx and is believed to have originated in water from cooling towers. The disease — which is a form of pneumonia, caused by the water-dwelling bacteria Legionella — is acquired by breathing in infected water vapors and mists in the air. It can show up in air conditioners, showers, faucets, hot tubs, cooling towers, and large plumbing systems.

This is the second major outbreak of the disease in the U.S. in a month. A Super 8 motel in Washington state voluntarily closed in early July after three cases of Legionnaires’ disease were linked to the establishment, the Associated Press reported.

Also known as Legionellosis, Legionnaires’ disease results in an estimated 18,000 hospitalizations in the U.S. each year, according to the Centers for Disease Control and Prevention, but experts say the number of people infected by the disease is much higher. “It’s a fairly common type of pneumonia in the U.S.,” board-certified infectious disease specialist Amesh A. Adalja, M.D., an assistant professor at the University of Pittsburgh Medical Center, tells Yahoo Health. Adalja says Legionnaires’ disease typically represents about 5 percent of pneumonia cases but is often underdiagnosed because the symptoms and treatment are similar.

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But Legionnaires’ isn’t transmitted from person to person. Officials say people are more in danger of contracting the disease from direct contact with the bacteria — which can show up in a lot of places. “It is something that’s very common,” says Adalja. “You even see it in puddles and mall water fountains.” The danger, he says, is when the concentration of the bacteria is high enough to make a person sick.

Outbreaks are more common in the summer and early fall, Adalja says, likely because people are exposed to air conditioners.

And, unfortunately, they aren’t all that rare. Two people in Chicago died in 2012 from Legionnaires’ disease, which officials believe they contracted from a downtown hotel. And a hospital in Rhode Island flushed its water supply last year after several patients developed the disease.

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Legionnaires’ disease has even shown up at the Playboy mansion. Two hundred people became ill after attending a party at the mansion in 2011, which officials say may have been caused by Legionella-infected smoke machines.

But not everyone who comes into contact with the bacteria actually develops Legionnaires’ disease. People who are older, smokers, and those with weakened immune systems are more at risk, according to the CDC.

Symptoms are similar to pneumonia’s and can include fever, chills, muscle aches, and cough. Some people may also experience headaches, fatigue, a loss of appetite, confusion, or diarrhea.

Worried you may be sick with Legionnaires’? Call your doctor. It’s typically treated (and cured) with antibiotics, but it can become serious if left untreated.

So should you be concerned about Legionnaires’ disease? Maybe. Says Adalja: “It’s not something that will ever really go away, because it’s a natural bacteria that’s in the water.”

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