(NEW YORK) -- New York City is experiencing another cluster of Legionnaires' disease just weeks after a cluster exposure in Manhattan was declared over.
So far, five cases and one death have been recorded, the New York City Health Department said on Thursday. Health officials said they are waiting for results for other potential cases.
Cases have been detected in the 10451 and 10456 ZIP codes, which includes parts of Melrose and Morrisania in the South Bronx.
The health department said it is actively investigating the cluster and that testing is underway for samples collected among cooling towers in the area.
Health officials are advising clinicians to be on the lookout for possible cases and to conduct testing if the disease is suspected.
An outbreak earlier this summer on the Upper East Side saw more than 90 cases and 11 deaths, which health officials found was linked to bacteria in some buildings' cooling towers.
"I understand that New Yorkers may have heightened concerns following the recent Upper East Side cluster," Dr. Alister F. Martin, NYC health commissioner, said in a press release. "We are taking immediate action. Water ecologists have sampled cooling towers in the affected area. Any cooling tower that tests positive will be directed to undergo full cleaning and disinfection immediately."
Legionnaires' disease is a severe form of pneumonia caused by inhaling the Legionella bacteria in small droplets of water mixed in the air or contaminated water accidentally going into the lungs.
The bacteria are found naturally in freshwater but amounts generally don't lead to disease. The bacteria typically grow best in warm water and in warm to hot temperatures, according to the Centers for Disease Control and Prevention.
The disease does not generally spread from person to person, but infections can occur if the bacteria get into a building's water supply, including in shower heads, sink faucets, hot water tanks, heaters, cooling towers and other plumbing systems.
Legionnaires' disease has increased in prevalence over the last decade, reaching a peak of 2.71 cases per 100,000 in 2018, the CDC said. Cases dropped during the first year of the COVID-19 pandemic and then rebounded in 2021.
Although most people recover from Legionnaires' disease with antibiotics, certain patients -- including those who are immunocompromised or who suffer from chronic lung diseases -- can develop complications that can be fatal.
About one in 10 people who develop Legionnaires' disease will die from complications, according to the CDC. Among those who develop Legionnaires' disease during a stay in a healthcare facility, about 1 out of every 4 people will die, the federal health agency added.
Health officials said any New Yorkers who live or work in the affected area, or visited since late August, should contact a healthcare provider immediately if they develop symptoms, such as fever, cough, shortness of breath or muscle aches.
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