The Legionnaires’ disease cluster in the Bronx that took the lives of two New Yorkers and infected 28 others is over, the city’s health department announced Friday.

No new cases have been identified in the area in the last four weeks, according to a health department investigation that is now closed. A total of 28 people were hospitalized in connection to the cluster, 24 of them have been discharged.

Legionnaires’ disease is a type of pneumonia caused by Legionella bacteria, which grows in warm water. The disease has flu-like symptoms and is contracted by breathing in water vapor containing the bacteria. It can’t be spread person to person.

Through molecular analysis of Legionella bacteria samples from human and cooling tower specimens, the health department’s public health laboratory and epidemiologists were able to find the source of the cluster in a cooling tower located in Highbridge. It has since been disinfected by the owners, under orders from the city. According to the health department, it’s working with the owners on long-term management.

In response to a 2015 outbreak of Legionnaires’ disease that infected 138 people and killed 16 in the South Bronx, the city passed a law that requires all building owners to register, maintain and test their cooling towers.

While the current cluster is over, the health department encourages anyone with flu-like symptoms to seek care immediately.