UPPER EAST SIDE, Manhattan (PIX11) — The city is doubling down on efforts to contain the spread of Legionella bacteria as the number of people who have tested positive for Legionnaires’ in New York City has continued to rise.

The outbreak has left residents on edge, with many worried about how soon the water towers used as cooling centers will be cleaned out.

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As of Sunday night, 59 people had tested positive for the disease — 15 of them still in the hospital. 33 have been discharged.

The city has now zeroed in on 31 locations across the Upper East Side that tested positive for Legionella bacteria. All of the locations have been cleaned out as of Monday morning.

Doctors are warning that the number of cases will likely grow.

“From the time of exposure to the Legionella bacteria to developing symptoms, it can take anywhere from two to 14 days to show symptoms of the infection. So on average, it’s about five to six days for most people,” said Dr. Deena Gupta-Adimoolam.

Legionnaires’ disease is not transmitted between people. Instead, people become infected by breathing in contaminated water mist.

Older adults, smokers, and those with compromised immune systems should pay attention to the symptoms, which include fevers, cough, shortness of breath, difficulty with breathing, muscle aches and pains, and fatigue.

The city has tested over 180 towers across three zip codes on the Upper East Side and hopes to complete more tests over the next few days to determine when and how the outbreak started.

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