Residents living in a Morris Heights apartment building are growing more concerned after two tenants tested positive for Legionnaires' disease.

Tenants at 1600 Sedgwick Ave. received a letter from the Health Department Monday alerting them to the positive results. The two cases were about 12 months apart from each other.

The Health Department held a meeting Monday at the building regarding its water supply, which is now being tested for legionella, the bacteria that causes the type of pneumonia known as Legionnaires' disease. While the tests are being conducted, residents at the building are advised to take baths instead of showers and to not use hot water when cooking. The department stresses that Legionnaires' is not contagious -- as it is spread through mist, not person to person -- and is easily treatable with antibiotics.

The announcement comes after an outbreak last year in the South Bronx led to major changes by the city to help prevent the spread of the disease.

Following that massive outbreak, the Health Department says preventative measures have been taken this year. Those measures include testing cooling towers every 90 days for legionella; notifying the community faster when there is a confirmed case; and lab testing if an outbreak occurs.

The Health Department tells News 12 that hundreds of cases of Legionnaires' do occur in the city every year, and that tenants are notified when two or more cases are confirmed at a single address in a one-year-period.