NEW YORK (CBSNewYork) — The New York City Department of Health and Mental Hygiene said Tuesday that it was investigating two cases of Legionnaire’s disease at a building in Rego Park, Queens.

The department said the cases came at the same address within a 12-month period. The department did not specify the address in a news release, though DNAInfo reported the address at 93-10 Queens Blvd.

“While the risk of infection to tenants is very low, as part of the routine protocol to assess potential sources of Legionnaires’ disease, the Health Department is working with the building management to test the building’s water supply,” the Health Department said in a statement.

The department said the two Rego Park patients were diagnosed six months apart. One remained hospitalized as of Tuesday, while the other had been discharged.

As per protocol, tenants at the building have been notified in multiple ways, the department said. The department is also testing the water.

Legionnaire’s disease is a type of pneumonia caused by Legionella bacteria, which is found in water systems – including indoor plumbing. The disease is not contagious and is easily treatable with antibiotics, the department said.

People get sick only by breathing in water vapor containing the bacteria, the department said. Adults with flulike symptoms, fever, cough, or difficulty breathing should seek immediate medical attention, the department said.

Those at highest risk are people age 50 or older who smoke cigarettes, have lung disease, or weakened immune systems.

Earlier this month, two cases of Legionnaires’ disease were also reported at a building in the Latimer Gardens public housing development on 137th Street in Flushing. The patients were diagnosed 10 months apart, the Health Departent said.

The city started regular, mandatory inspections of cooling systems after a deadly Legionnaires’ outbreak in the South Bronx two-years-ago. In that case 12 people died.

Other recent legionnaires cases were reported in June in Lenox Hill and Harlem.

For more information on Legionnaire’s, click here.