Health officials in New York City say a cluster of Legionnaires’ disease in Central Harlem has grown to 99 cases, including four deaths.

The last of 12 cooling towers that tested positive for the bacteria currently spawning a Legionnaires’ outbreak in Harlem is being remediated Friday, with officials hoping containment efforts will help prevent another death.

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.