NYC Legionnaires' Disease Cases Spiked 64% In 2017, Data Show

NEW YORK, NY — Legionnaires' disease sickened more than 400 people in New York City last year as the state continued to lead the nation in cases of the illness, federal data show.

The five boroughs reported 441 Legionnaires' disease in 2017, a 64 percent spike from the 268 reported in 2016, according to figures from the Centers for Disease Control and Prevention. That also surpasses the total from 2015, when the worst outbreak in city history sickened 133 people and killed 16 in the Bronx.

The city accounted for nearly 44 percent of the 1,009 cases statewide, data show. That's more than any other state in the nation and a 38 percent increase from 2016 levels.

Legionnaires' disease is an aggressive form of pneumonia caused by the legionella bacteria, which thrives in warm, wet places such as old cooling towers and air-conditioning systems.

City and state health officials say the higher numbers don't necessarily mean more New Yorkers are getting the potentially deadly disease. They attributed the spike to increased awareness, better testing and more robust reporting. But aging populations and infrastructure may also play a role, they said.

"NYC is the most aggressive in following up on all legionella cases reported to us and we try to obtain exposure history for all our cases," Christopher R. Miller, the press secretary for the city Department of Health, said in an email. "This is not true for all US jurisdictions, which means we do not have a complete picture of legionella-related disease in the US."

The increased prevalence of Legionnaires' in New York City follows a national trend — reported cases have risen steadily across the country since 2000, according to the CDC.

The city saw two large Legionnaires' outbreaks last year, according to the Alliance to Prevent Legionnaires' Disease, a nationwide advocacy group. One on the Upper East Side killed one person and sickened six others in June. At least a dozen people in Flushing, Queens caught the disease in October.

The state Department of Health started regularly checking cooling towers and drinking-water systems in hospitals and nursing homes after the 2015 Bronx outbreak. Some 57 percent of the state's legionella cases start in those facilities, the department said.

But the Alliance for the Prevention of Legionnaires' Disease argues New York hasn't done enough to stop the bacteria from entering buildings from public water systems, which they say cause 35 percent of Legionnaires' disease outbreaks. Health officials also focus too much on outbreaks while neglecting "sporadic" cases of the illness, which account for 96 percent of reported cases nationally, the group says.

"We are convinced that any meaningful reduction in Legionnaires’ disease in New York requires a focus on the complete water distribution system that supplies our homes and workplaces—from source to consumption," Daryn Cline, a spokesperson for the alliance, said in a statement.

(Lead image: A cluster of legionella bacteria, which causes Legionnaires' disease. Photo from Centers for Disease Control and Prevention)