[Legionnaires disease: history of the discovery, the main stages of the study pathogen and infection].

The article discusses main directions and stages of the 45 years of Legionnaires disease study. Analysis of epidemiology and laboratory diagnostics of infection show as unknown until 1976 microorganism occupied a notable niche in the etiology of severe pneumonia. Control and monitoring of potential dangerous water systems, generating water aerosol containing Legionella in high concentration, plays a major role in the prevention of Legionnaires disease.