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

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.

Health officials in New York City say a cluster of Legionnaires’ disease in Central Harlem has grown to 99 cases, including four deaths.