SMITHTOWN, N.Y. (CBSNewYork/AP) — The potentially deadly bacteria have been found in the cooling towers at both Smithtown East and Smithtown West high schools, school officials said.

As CBS2’s Dave Carlin reported, the Smithtown School District superintendent said after a thorough cleaning, the threat is gone. But some parents are not so sure.

“It was just like, everyone was a little bit on edge,” said Smithtown East sophomore Heather Shifflett, 15.

Shifflett said she is breathing easier now the school day is over, after being in class at a school where the bacteria were deteted.

Parents also received a robocall from schools Supt. Dr. James Grossane.

“Upon receipt of the results yesterday, the towers were immediately shut down and disinfected by licensed professionals,” Grossane said in the robocall.

“They re-tested it, and it tested negative, so everything should be working fine now,” a woman said outside the school.

There were no reports of Legionnaires’ disease at any of the Smithtown district schools. The testing was conducted as a response to the Legionnaires’ outbreak in the Bronx that has killed more than a dozen people since July.

The state Department of Health issued emergency regulations requiring the testing.

“It’s not a disease to be taken lightly,” said Smithtown parent Pat Zanfardino.

Some parents said they are not content to let the school district have the final say on this, and they want more documentation.

“To have an actual document showing exactly what it was would be nice,” said parent Erika Roos.

“My daughter’s not going to come back until I hear from the department of health,” added Zanfardino.

But a grandfather of a student said, “They did it it’s not hard to clean it up.”

The district said the threat is over, testing will be ongoing, and it’s time to get back to the books.

Meanwhile, a new cluster of Legionnaires’ disease cases in the Morris Park section of the Bronx has claimed the life of one person. The number of confirmed cases in the neighborhood has grown to 13.

Legionella bacteria in a hotel cooling tower caused an outbreak of the disease in the South Bronx over the summer that contributed to at least 12 deaths.

New York City Health Commissioner Dr. Mary Bassett has said she doesn’t believe the Morris Park cases are connected to the earlier outbreak.

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. The city says its drinking water supply has not been affected.

It is spread through contaminated mist and cannot be spread from person to person.

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