HARLEM, Manhattan (WPIX) – A fourth person has died amid an outbreak of Legionnaires’ disease in Harlem, health officials in New York City have confirmed.

The outbreak had sickened at least 99 people as of Thursday, 17 of whom were hospitalized, officials said.

Legionnaires’ disease is a type of pneumonia that is caused by Legionella bacteria, which grow in warm water and spread through building water systems. The city's outbreak has been linked to cooling towers, which use water and a fan to cool buildings.

Health officials disclosed Thursday that 12 cooling towers in Harlem buildings had tested positive for the bacteria. Those buildings included Harlem Hospital, a city health clinic, a popular retail center on 125th Street, a CUNY college science building and the Harlem condo center o

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