[Surveillance and prevention of nosocomial Legionella pneumonia].

Statens Serum Institut surveys the occurrence of nosocomial pneumonia caused by Legionella. The rate is low compared to other nosocomial infections but carries a high mortality. Verification of the diagnosis and acquisition (nosocomial or community acquired infection) is carried out in each suspected case. The criteria used for classification are described. Preventive measures include protection of susceptible patients as well as maintenance of the hot-water supply providing a minimum temperature of 50 degrees C at any hot tap. Technical solutions to reduce the concentration of Legionella in hospital hot-water supply systems are listed, and a guideline for the control and surveillance of the occurrence is suggested.