What To Know About The Upper East Side's Legionella Building List

UPPER EAST SIDE, NY — As landlords work to disinfect the remaining 19 Legionella-contaminated cooling towers on the Upper East Side by Thursday, many are left wondering what it means if their apartment building, workplace or a neighborhood business appears on the list.

Health officials say a building's inclusion does not mean it has been identified as the source of the outbreak, which started on July 2 and has sickened 63 people so far.

Instead, the list of 76 buildings identifies where an initial screening detected Legionella bacteria, triggering mandatory cleaning and disinfection while more definitive testing continues.

Fifty-seven buildings have been fully remediated already, and the remaining 19 will be remediated by Thursday, officials said.

Patch spoke with Dr. Dana Mazo, an infectious disease specialist at NYU Langone Health, about what residents should know — and what they don't need to worry about.

What Does It Mean If A Building Is On The List?

The city is using two different tests to investigate cooling towers.

The first, called a PCR test, detects DNA from Legionella bacteria. A positive result confirms the bacteria's genetic material is present but does not determine whether the bacteria are alive or capable of causing illness.

The second test, known as a culture test, can take up to two weeks. It determines whether live Legionella bacteria are present and, if so, how much is in the cooling tower. Those results will help investigators determine whether any of the buildings are actually linked to the outbreak.

"Knowing where some of the addresses where it's tested positive, it can help sort of localize the exposure a little bit," Mazo said. "Someone can say, 'Hey, I work in that building and I have these symptoms,' or, 'I live near that building.'"

What Happens After A Cooling Tower Tests Positive?

Residents don't need to pressure building managers to take action.

Any building that receives a positive PCR test is immediately ordered by the city to drain, clean and disinfect its cooling tower — even before culture results are available.

"If it's tested positive, they are doing remediation and cleaning," Mazo said.

Health officials have said they expect the latest round of cleanings to be the final remediation effort needed to contain the outbreak, which began July 2 in ZIP codes 10028, 10128 and 10075.

Is It Safe To Drink The Water Or Use My Air Conditioner?

Yes.

The outbreak is linked to contaminated mist released from cooling towers — not drinking water, home plumbing or residential air-conditioning units.

"You can still drink water, bathe, cook. You can still use the water. You can still use your air conditioning," Mazo said.

City health officials have also said splash pads, swimming pools and playground sprinklers remain safe to use.

Should I Be Worried If I Live Near One Of These Buildings?

Not necessarily.

Mazo said the overall risk to the public remains low. However, knowing whether you've spent time near one of the buildings can help you and your doctor evaluate possible exposure if you develop symptoms.

"The overall risk to the public is still low," she said. "However, if you have spent time in these neighborhoods, the key thing to do is to monitor yourself for the symptoms."

What Symptoms Should I Watch For?

Legionnaires' disease is a severe form of pneumonia caused by Legionella bacteria, which thrive in warm, humid environments such as cooling towers.

People become infected by breathing in contaminated mist. The disease does not spread from person to person.

Symptoms typically include fever, chills, cough, muscle aches, and shortness of breath. Some people also experience headaches, fatigue, loss of appetite, confusion or diarrhea.

Who Is Most At Risk?

People who are 50 or older, smoke or vape, have chronic lung disease or have weakened immune systems are at the highest risk of becoming seriously ill, officials said.

In addition to residents of the three affected ZIP codes, anyone who visited the east side of Central Park between East 76th and East 97th streets since late June should monitor themselves for symptoms, officials said.

The disease is extremely rare in children, and never present in pets, health officials said.

Health officials recommend that anyone who has spent time in ZIP codes 10028, 10128 or 10075 — including visitors to the east side of Central Park between East 76th and East 97th streets — monitor themselves for symptoms.

"If you develop those symptoms, make sure to call your physician or get evaluated at urgent care," Mazo said. "If you're really sick, go to the emergency department."

For questions, email Miranda.Levingston@Patch.com.

Related content:

• What To Know About The UES Legionnaires' Outbreak
• 76 UES Buildings Test Positive For Legionella: See New List