Rainwater left untreated in cooling towers atop city-owned Harlem Hospital fueled the Big Apple’s deadliest Legionnaire’s disease outbreak in a decade, the Rev. Al Sharpton charged Tuesday.

The death toll in New York’s ongoing outbreak of Legionnaires' disease in Central Harlem has risen to five, as more people continue to be diagnosed with the severe pneumonia.

A fifth person has been killed by the Legionnaire’s disease outbreak ripping through Harlem, which has also sickened more than 100 others, health officials announced.

A fifth New Yorker has died in the Legionnaires’ disease outbreak in Harlem, city health officials said.

A fifth person has died as a result of the Legionnaires’ disease outbreak in Harlem, which has sickened more than 100, health officials said.