NYC public health experts concerned over drop in legionella inspections under Mayor Adams

Public health experts have expressed concern over a dramatic decline in inspections for legionella bacteria preceding a recent outbreak in Harlem that's killed three people and hospitalized more than 20 others.

A Gothamist analysis found the city has conducted fewer and fewer inspections each year since Mayor Eric Adams took office. This year, the city’s Department of Health and Mental Hygiene is on track to complete just half the number of inspections it did in 2022. That year it inspected 4,443 cooling towers, which can spread legionella, and issued more than 2,900 violations to building owners. The health department blamed staffing shortages for the decrease.

Janet Stout, a University of Pittsburgh professor specializing in prevention of Legionnaires’ disease, said regulations implemented in 2017 after a previous outbreak put New York City’s prevention and monitoring measures ahead of other municipalities. But she said she was concerned by the steep drop in inspections in the years since the rules were implemented.

“A 50% reduction feels a little extreme,” she said. “It makes a lot of sense that after implementing the regulation, there would be more inspections and more fines.”

According to Stout and other experts, regular city inspections help ensure building owners are testing and cleaning their towers regularly, as required by law. Legionella bacteria can grow to dangerous levels within two weeks, and Stout said enforcement of regular testing is critical.

Abraham Cullom, director of safety management at water-testing company Pace, said it was unclear whether the decrease in inspections directly led to the current outbreak.

“It certainly raises my hackles,” he said. “It’s possible that more inspections could have prevented this outbreak, but you can’t say that for certain because these problems can manifest within weeks.”

A spokesperson for City Hall said that while the enforcement efforts have shrunk due to staff shortages, the city has had enough inspectors to respond to the outbreak.

William Fowler, deputy press secretary for Mayor Eric Adams, said the health department was able to test all the cooling towers in the affected ZIP codes. If Legionella bacteria was found, the city required building owners to clean and disinfect the towers within 24 hours.

When asked whether more regular or frequent inspections could have prevented the current outbreak, Fowler said, "It’s hard to say exactly what would have prevented an outbreak." He added that the health department was continuing to recruit inspectors.

Cooling towers typically sit atop large apartment buildings as part of their HVAC systems. The towers circulate water through the building, absorbing heat and returning it to the top of the building, where it evaporates. But the warm water can amplify the growth of legionella bacteria, which can vaporize into the air around the building.

When inhaled, the bacteria can cause Legionnaires’ disease, a type of pneumonia with symptoms like fever, cough and fever. The current Harlem outbreak has sickened a total of 83 people, according to city officials.

The current regulations were introduced after a historic outbreak killed 16 and sickened 138 in 2015. The law requires building owners to develop treatment and maintenance plans for their cooling towers, test regularly and report samples to the health department. The law also authorized the department to conduct its own investigations.

Bill Pearson helped develop the standard on legionella risk management from the American Society of Heating, Refrigerating and Air Conditioning Engineers, a professional organization that conducts research and develops industry guidelines. That standard, which informed the city’s law on water cooling tower management at the time it was drafted, relies on building owners to conduct regular testing.

“ If somebody has a great plan and they put it up on the top of a shelf, you know, I would consider that negligent," Pearson said.

"You must validate that you have controlled legionella," he added. "That's where the testing comes in."

Stout said outbreaks can be eliminated with a combination of government enforcement and building maintenance, noting building owners are just as responsible as city officials for preventing outbreaks of Legionnaires’ disease. Owners are required to report test results to the health department every three months.

The city also requires building owners to clean and test their water systems for other types of contaminants on a weekly basis with the help of a qualified individual. Stout said owners typically hire testing companies. If a testing company finds unusual levels of bacteria, the building's owners are required to conduct subsequent testing. To pass a city inspection, owners must show records that they’re cleaning and testing regularly.

“Prevention is achievable,” she said. “It’s just, can we get humans to do what they’re supposed to do?”

Chantal Gomez, a spokesperson for the health department, said it aims to inspect towers once a year. Yet, out of the 4,928 registered cooling towers in the city, 1,922 have not been inspected since 2023, according to a Gothamist analysis of city data.

Cullom said it’s essential for health departments to have adequate staff to prevent outbreaks of Legionnaires’ disease.

“This drives home the point that folks doing work in public health are providing a huge, huge service to society,” he said. “Making sure that those departments and those people can do the work is really important.”

Caroline Lewis contributed reporting.