Nosocomial Legionnaires' disease - strategies for prevention

Colonization of water systems by Legionella spp. is ubiquitous in hospitals throughout the world. Nevertheless, the consequences of this situation are variable. In some hospitals nosocomial pneumonia caused by Legionella pneumophila is a rare event, whereas this pathogen causes epidemics in others and results in significant morbidity and mortality. In hospital wards where immunosuppressed patients are treated, hot water systems should ideally be free of Legionella contamination. Risk assessment for this disease forms the basis for the institution of control measures. Detection and quantification of Legionella spp. in the environment, in particular in the hospital water distribution system is one of the cornerstones of risk assessment. Despite the existence of guidelines for the prevention of this nosocomial infection, many methodical and technical aspects of surveillance and prevention are not standardized. This review, summarizes the current state-of-the-art regarding these aspects and points out important areas which require further study. (C) 1998 Elsevier Science B.V.