World Health Organization World Health Organization website World Health Organization website World Health Organization Fact Sheet Legionnaires Disease World Health Organization fact sheet World Health Organization: Legionellosis World Health Organization http://www.who.int/mediacentre/factsheets/fs285/en/ http://www.who.int/mediacentre/factsheets/fs285/en/ World Health Organization: Legionellosis «http://www.who.int/mediacentre/factsheets/fs285/en/»2 World Health Organization World Health Organization website http://www.who.int/mediacentre/factsheets/fs285/en/ World Health Organization website