[Legionella infection in occupational and environmental health]

Air condition systems are indispensable for amenity in the work environment. It is known that Legionella species are widely distributed in the water of cooling towers, and that the bacteria are responsible for community-acquired pneumonia (Legionnaires' disease) and for influenza-like symptoms (Pontiac fever). Furthermore, Legionella species are associated with building-related illness. In Japan, however, prevention and countermeasures are inadequate against legionellosis compared to those of Europe and the USA. This is because occupational and environmental medicine in Japan has not been based on a microbiological point of view, and that workplace inspections have not covered cooling towers. Therefore, Legionella species in the water of coolig towers have not been routinely monitored in the work environment. This review describes the microbiological characteristics of Legionella species, their habits in the environment, the source and route of infection, the pathogenesis, the symptoms and treatment of legionellosis, outbreaks of this disease throughout the world, and how to deal with this organism in the work environment to prevent legionellosis.