LENOX HILL — After Legionnaires' disease recently killed an elderly woman and sickened seven others, the city has identified 24 neighborhood cooling-tower systems that contained low levels of Legionnella bacteria, according to a fact sheet the Department of Health sent out to elected officials Monday.
All 116 cooling tower systems in Lenox Hill were tested, and of those, 42 had traces of Legionella DNA, which doesn't necessarily mean that there was bacteria to make people sick. Nonetheless, those systems were disinfected, officials said.
Of the 42 that tested positive for Legionella DNA, 24 actually had low levels of Legionella bacteria that can potentially cause human disease, according to the DOH. Those were cleaned and disinfected.
The DOH did not specify where those towers are located because it hasn't yet identified a DNA match between a patient and cooling tower sample. That testing is ongoing, officials said in the fact sheet.
An additional person became ill one June 16, before the towers were ordered to be cleaned, marking it eight total Legionnaires' disease contractions in the area.
On June 16, the DOH identified a cluster of Legionnaires' disease within a half-kilometer radius of the Lenox Hill neighborhood and tested the cooling towers within the neighborhood.
Three days later, the department determined the bacteria likely spread from mist that the cooling towers emitted and not from drinking or bathing water, officials noted during a panel discussion at the Lenox Hill Neighborhood House.
As soon as news of the cluster broke, on June 16 and 17, the DOH met with the public, went door to door and called residents in the 10021 zip code about the cluster, the sheet says.
DOH spokesman Christopher Miller said the investigation of the cluster officially ended on Monday.
"Approximately 100 Health Department personnel were involved in the response as they sought to prevent additional cases and raise awareness," he said in a statement. "The Health Department has the most sophisticated disease monitoring system of any municipal health department in nation — every day, disease detectives monitor hospital emergency departments and laboratory reports for over 75 reportable diseases, and water ecologists quickly respond to environmental hazards related to Legionnaires’ and other diseases to keep New Yorkers safe.”
This is the city's latest case of Legionnaires' disease, after an outbreak was discovered within East Harlem's 23rd Precinct stationhouse.
The city receives an average of 200 to 400 reports of the disease per year, officials said. In 2016, there were 269 cases compared to 438 in 2015 and 225 in 2014, DOH numbers show.
The largest outbreak happened in 2015 in the South Bronx, killing 12 people and sickening more than 120.
That outbreak was traced to 15 cooling towers, prompting new legislation from the city that requires cooling towers to be tested for the bacteria quarterly and for the Health Department to do annual surprise inspections.
Officials continue to warn people not to ignore symptoms like headache, fever and coughing, as well as fatigue, loss of appetite, confusion and diarrhea, noting that symptoms appear two to 10 days after “significant exposure” to the Legionella bacteria.