NEW YORK - At least 10 people have died from the Legionnaires' disease outbreak in New York City, and a new case has been found out of state.

The source of the outbreak has been linked to five poorly maintained cooling towers in the South Bronx. Maintained properly, they are needed to help massive air conditioning units run effectively. If they're not cleaned and treated, they can collect harmful bacteria and cause the disease. 

The New York state health commissioner announced Friday afternoon that the state is working on new guidelines for maintaining cooling towers. The Nassau and Suffolk health commissioners were at the news conference as well.

Assistant Director of Engineering at North Shore University Hospital Sam Fischer says businesses with a cooling tower should be using the correct chemicals, just like how a swimming pool is treated.

"Once a year we turn it off, drain it all down, power wash it inside and out," said Fischer. "We test it once a year of legionella and every two weeks for bacteria."

Health officials on Long Island are urging all property owners with cooling towers to have them regularly inspected and cleaned.