South Bronx Legionnaires’ disease outbreak declared over, following 2 deaths

City health officials on Wednesday declared the end of the South Bronx Legionnaires’ disease outbreak, saying residents and visitors to the area are no longer at increased risk of contracting the severe form of pneumonia.

The officials said in a statement the source of the outbreak had been eliminated, after ordering widespread testing and cleaning of water cooling towers in the Melrose and Morrisania communities. The outbreak sickened 23 people, two of whom died.

The city identified the outbreak earlier this month, specifically in the ZIP codes of 10451, 10455, 10456 and 10459. Of those who contracted the disease, 21 were hospitalized. Two people remain in the hospital.

“The increased risk of exposure has ended, and the source has been eliminated, but our work is not over,” Dr. Alister Martin, the city health commissioner, said in a statement. “We will hold accountable any cooling tower operator who fails to follow the rules of this city and jeopardizes the health of New Yorkers.”

The city health department said the Bronx outbreak, like other large clusters in recent years, was caused by a water-cooling tower contaminated with Legionella bacteria. Cooling towers can emit the bacteria into the air with water vapor, which can then infect passersby.

Through culture tests, the city identified seven cooling towers in the affected area that tested positive for live Legionella. All were cleaned and disinfected more than two weeks ago, according to the city health department.

Local laws require the owners of buildings that have cooling towers to put in place maintenance plans to prevent the growth of Legionella and to submit regular test results for the bacteria to the city.

But even with these laws in place, Legionnaires’ disease remains a major public health concern in the five boroughs. The South Bronx outbreak came on the heels of another deadly outbreak of the disease that was identified in early July on the Upper East Side. That outbreak infected more than 90 people and killed 11.

City councilmembers have proposed additional legislation to improve Legionnaires’ prevention and public health communication around the disease.

Additional testing is needed to identify the cooling tower that caused the South Bronx outbreak, which the city health department estimated would be completed by late fall.