Three individuals have now died this week in a rapidly expanding cluster located in central Harlem, Manhattan, according to the New York City Health Department. At least 64 other people have been diagnosed with Legionnaires' disease since July 25.

The cases are clustered in five ZIP codes in central Harlem, the health department said, and a spokesperson said the outbreak is not expected to spread to other communities.

Adults who have been in the affected area since late July with flu-like symptoms, fever, cough, or difficulty breathing should seek immediate medical attention, health officials say.