Legionella in the City

Aug. 6, 2015

An outbreak of Legionnaire’s disease in New York City has prompted discussion about cooling towers’ role in the spread of Legionella bacteria and whether the city should do more to prevent future outbreaks.

According to the New York Times, the current outbreak is the largest in the city’s history, with seven deaths from the disease and 86 people sickened as of Tuesday. All of those who have fallen ill live in the South Bronx, and although the source of the outbreak is still under investigation, five cooling towers that have tested positive for Legionella are the suspected culprits.

So far, the city’s response to Legionnaire’s disease outbreaks has been reactive rather than proactive, leading community leaders and residents to call for more stringent regulations and inspections of cooling towers. According to the article, Dr. Jay Varma, deputy commissioner for disease control for the New York City health department, said in an interview that creating such regulations could be difficult due to the nature of the disease—the source cannot always be determined, and cooling towers are not always at fault.

The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) recently introduced guidelines that could help. ANSI/ASHRAE Standard 188-2015, Legionellosis: Risk Management for Building Water Systems, includes minimum risk management requirements for buildings’ potable and non-potable water systems, detailed requirements on legionellosis control strategy goals, and guidelines on how to document control strategies.

What is your opinion on the New York City Legionnaire’s disease outbreak? Should the city government implement regulations on cooling towers to help avoid future outbreaks? Let us know your thoughts in the comments, or send us an e-mail at [email protected].