The Legionnaires' disease outbreak in Central Harlem has been traced to 12 cooling towers, including several at city-run buildings like Harlem Hospital, officials said Thursday.

A fourth person has died in connection with a Legionnaires’ disease outbreak in New York City. Health officials disclosed the latest death Thursday as they revealed that some cooling towers tested positive for the bacteria in some city-run buildings.

A Legionnaires' disease cluster in the Harlem area of New York City has caused four deaths and sickened nearly 100 people. Here's what it is, symptoms and how it's spread.