November 20, 2015

Press Release # 055-15
Friday, November 20, 2015

(347) 396-4177,,

Health Department Identifies Likely Source of East Bronx Legionnaires' Disease Outbreak

Legionella strains from Bronx Psychiatric Center cooling tower match strains taken from patients; the Psychiatric Center’s cooling tower was disinfected immediately and is currently offline for winter

November 20, 2015 – The New York City Health Department today announced that it had identified the likely source of the Legionnaires’ disease outbreak in the East Bronx. After extensive sampling of cooling towers and testing of Legionella bacteria, the city’s Public Health Laboratory, in collaboration with the state’s Wadsworth Center laboratory, identified a cooling tower at the Bronx Psychiatric Center as the likely source of the outbreak. The Legionella strain found in the cooling tower matched samples taken from four patients.

The Psychiatric Center has cooperated fully with all agencies involved in the investigation, has cleaned and disinfected its tower, and is working with the Health Department on a long-term maintenance plan that is consistent with industry standards. The tower was inspected and disinfected on August 5 in compliance with the New York City and New York State regulations, and a test from August 17 showed no sign of legionella. They have also retained maintenance consultants to prevent the growth of Legionella in their cooling tower. The Psychiatric Center has and will continue to work diligently to maintain compliance with state and city requirements. There have not been any further outbreak-related cases of Legionnaires disease with illness onset after September 28.

“Using the expertise and resources of the city and state’s laboratories we were able to identify the DNA fingerprint of the outbreak strain and match it to samples we received from patients linked to the outbreak,” said Health Commissioner Dr. Mary T. Bassett. “The Psychiatric Center worked diligently to clean and disinfect the cooling tower as soon as it tested positive for the disease causing Legionella. All cooling towers across the affected area were evaluated and disinfected as needed. We continue to remain vigilant for any signs of Legionella in the Bronx and across the city. We know that because Legionella exists in the environment we will continue to see sporadic cases of Legionnaires’ disease in the city, but the disease is curable with common antibiotics.”

Overall, the geographic distribution of cases was consistent with community-wide exposure to a contaminated aerosol. Patient and family interviews did not identify a common exposure among the cases other than living or spending time in the outbreak area.