Chapter 8 : Nosocomial Legionella Infection in the County of Copenhagen, 2000–2004

Abstract:

In Denmark (5,400,000 inhabitants), Legionella infection is a notifiable disease. Two departments at Statens Serum Institut (SSI) in Copenhagen are involved in collecting data about these cases, since (i) notifications based on clinical and local laboratory data are sent to the Department of Epidemiology; (ii) all cultured Legionella patient isolates are referred to the Department of Bacteriology, Mycology, and Parasitology (ABMP) from local departments of clinical microbiology for confirmatory identification and serotyping; and (iii) water samples from environmental investigations are sent to AMBP for culture and DNA typing. Every local clinical microbiology department in Denmark has its own infectious disease control unit, which is responsible for the surveillance and investigation of nosocomial infections. The diagnosis of Legionella infection was made by the detection of Legionella species in respiratory specimens by PCR, a positive urinary antigen test, or a significant rise in antibody titre. Diagnostic results and clinical data, including onset of disease and location of the patients, were retrieved from the laboratory information system at DCM Herlev. During the period of 2000 to 2004, several efforts were made to combat nosocomial Legionella infection, such as increasing the hot water temperature and replacing hot water tanks with heat exchangers.