A deadly Legionnaires' disease outbreak in New York City has set health and community leaders on a campaign to educate the public on ways to prevent the bacteria from growing and spreading.

At least 24 people remained hospitalized nearly two weeks after the cluster of Legionnaires’ disease was first detected in Harlem, with five zip codes affected, city health officials said.

Here’s what to know about Legionnaires’ disease, how it spreads, and the East Harlem cooling tower outbreak under investigation.