Legionnaires
An outbreak of Legionnaires' disease, which is spread through water droplets contaminated with Legionella bacteria, shown above, has killed 10 people in New York City. Officials ordered inspections Thursday for all buildings with cooling towers, which have been linked to the current outbreak. U.S. Centers for Disease Control and Prevention

All city buildings with cooling towers must inspect and disinfect them within 14 days, New York City Mayor Bill de Blasio ordered Thursday. The state would provide these testing services free of charge to eligible buildings not just in New York City but throughout the state, Gov. Andrew Cuomo's office said. The city is grappling with an outbreak of Legionnaires’ disease in the South Bronx in which 10 people have died and more than 100 have taken ill so far.

Owners, operators and managers of private buildings with cooling towers or units could get free testing for Legionella bacteria through October, Cuomo's office said in a statement. The testing would be conducted at the New York State Health Department’s Wadsworth Center Laboratory in Albany, New York. The outbreak has been traced to six New York City sites where cooling towers tested positive for Legionella bacteria.

Legionella bacteria thrive in warm water and wet environments like water systems, whirlpool spas and cooling towers. They are also found in the natural environment, such as in creeks and ponds, but are particularly dangerous when they occur in high concentrations. The bacteria are transmitted through water droplets, not from person to person.

“We expect building owners to be responsible for cleaning and maintaining their cooling towers and we intend to hold them responsible for the spread of any disease,” Cuomo said in a statement Thursday. "Providing free testing should help restore the public’s confidence that government is taking every precaution possible."

Legionnaires’ disease acquired its name after an outbreak of the disease in 1976 was traced to a Philadelphia hotel that was hosting an American Legion convention. Cases of the bacterial infection, which can cause severe pneumonia, have been confirmed as far back as 1947.

New York state sees an average of 539 cases of Legionnaires’ disease per year. “This is not a new phenomenon,” Cuomo said, even as he acknowledged that the most recent outbreak of Legionnaires’ was the largest in the state’s history.

Health officials are investigating sites in the Bronx that were found to have large concentrations of Legionella bacteria and are expected to share their findings with state and city officials next week.