title: A major focus of Legionnaires' disease in Bloomington, Indiana.
abstract: Thirty-nine cases of Legionnaires' disease in a 16-month period were identified in visitors to and residents of Bloomington, Indiana. Thirty-five patients had spent at least one night at the Indiana Memorial Union in the 2 weeks before becoming ill. Five of 32 sporadic cases nationwide between 1 January and 31 March 1978 were retrospectively shown to be in persons who had recently visited the Union. The risk of acquiring Legionnaires' disease as a Union visitor was at least 17 times greater than that for Bloomington residents 20 years or older. Employees who had worked at the Union 5 years or longer were more likely to be seropositive than workers in other Bloomington hotels. Legionnaires' disease bacterium was isolated from five environmental sites in Bloomington. A cooling tower may have been involved in disease spread, but it was not the only source. Hypochlorite solution was added to cooling tower water as a precautionary measure; however, one case was confirmed in a man with Union exposure 9 days after hypochlorite treatment had begun.
mesh_terms: D000328:Adult; D000368:Aged; D000389:Air Conditioning; D001419:Bacteria / Q000302:isolation & purification; D004196:Disease Outbreaks / Q000453:epidemiology*; D004203:Disinfection; D004781:Environmental Exposure; D005260:Female; D006801:Humans; D007196:Indiana; D007877:Legionnaires' Disease / Q000453:epidemiology* / Q000209:etiology / Q000635:transmission; D008297:Male; D008875:Middle Aged; D012306:Risk; D012973:Sodium Hypochlorite; D014495:Universities
chemical_list: D012973:Sodium Hypochlorite