Maryland issues guidelines for preventing Legionella

The Maryland Department of Health and Mental Hygiene in Baltimore recommends that acute-care hospitals routinely test water systems for the Legionella bacteria, that doctors have ready access to the proper diagnostic tools, and labs be required by law to report Legionnaires’ disease cases to the state.

The recommendations go beyond current Centers for Disease Control and Prevention guidelines, which recommend environmental testing only after a case of Legionella infection has been identified. These are some of the specific recommendations:

  • Acute-care hospitals should routinely perform "risk-based" environmental cultures for Legionella, including cultures of the hospital hot-water system.
  • All acute-care hospitals should have in-house capability to perform Legionella urinary antigen tests. If not, they should contract with a laboratory that will provide urinary antigen testing and results within 24-48 hours. Hospitals performing solid organ or bone marrow transplants or those caring for transplant patients should have the in-house capability to culture Legionella directly from patient specimens. All other hospitals should have a system in place to submit cultures to a microbiology laboratory within 24 hours of specimen collection.

Dept. of testing & eradication

The task force also studied methods for preventing Legionella infection and killing the bacteria when it is detected in hospitals. The panel recommended that health care facilities establish teams to handle environmental testing and eradication.

Hot water temperature limits should be raised to 122° F (from 110°, the temperature currently used by most hospitals) so that Legionella is less likely to survive. When new hospitals are built, or hospitals are remodeled, water systems should be designed to minimize the risk of Legionella infection.