Overall, there have been 114 confirmed cases of the disease, and six of those people are hospitalized.
The NYC Health Department is investigating the outbreak in central Harlem, in areas covered by ZIP codes including 10027, 10030, 10035, 10037, and 10039.
In the wake of the deadly Legionnaires' disease outbreak in Harlem, the State Health Department says it will "undertake a thorough review" of the city's response.
The outbreak has been linked to 12 cooling towers a number of them at city-owned buildings, including Harlem Hospital.
Scientists are using DNA to determine which cooling tower or towers made people sick.
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