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

The health department offered five ZIP codes in central Harlem -- 10027, 10030, 10035, 10037, 10039 – that were at the center of the cluster, as officials stressed the disease was airborne and could reach people even outside of the directly affected buildings.

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.