YONKERS, N.Y. (CBSNewYork/AP) — The bacteria that cause Legionnaires’ disease were found this week at the cooling tower at Riverside High School in Yonkers, the city announced Friday.

Legionella bacteria were discovered this week in the tower following the issuance of emergency regulations by New York state authorities, and an order by Yonkers Mayor Mike Spano to clean all cooling towers.

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The cooling tower has been cleaned and disinfected, and the building is open to administrators planning for the first day of school on Sept. 2. There were no reported cases of Legionnaires’ disease in Yonkers, but Spano emphasized that Yonkers officials are being proactive given the municipality’s proximity to the Bronx.

Twelve people died in a Legionnaires’ outbreak in the South Bronx this month. New York City said they pinpointed the source to the cooling tower atop the Opera House Hotel in Mott Haven.

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New York City officials also declared the outbreak over, saying there have been no new cases since Aug. 3. The incubation period for the disease is two to 10 days.

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Mayor Bill de Blasio this week signed new legislation into law aimed at regulating cooling towers in response to the outbreak.

The new law requires landlords to register, inspect and regularly clean cooling towers. Building owners would also need to get an annual certification. Those who do not comply would face fines up to $25,000, WCBS 880’s Rich Lamb reported.

Legionnaires’ disease — a form of pneumonia especially dangerous for the elderly and for people with underlying health issues — can usually be traced to places favorable to Legionella growth such as cooling towers, hot water tanks, whirlpool spas, hot tubs, humidifiers and condensers in large air conditioning systems. It is spread through contaminated mist and is not contagious.

Symptoms of Legionnaires’ disease include headache, fatigue, loss of appetite, confusion and diarrhea.

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