[Epidemiology of legionnaires' disease in Switzerland in 1988]

Both sporadic cases and outbreaks of legionnaire's disease have been reported. To date, no outbreaks have occurred but several case reports have been published in Switzerland. The newly organized surveillance system of notifiable diseases, introduced in 1987, makes it possible for the first time to analyze reported sporadic cases more precisely. In 1988, the laboratories reported a total of 32 cases with cultural or serologic proof of legionellosis. In 75% of cases patients were aged over 40 years, 78% occurred among males. The majority of them were known to be smokers. In 9 cases an underlying predisposing condition was known: hairy cell leukemia (3 cases), immune hemolytic anemia (1), type 2 diabetes (2), chronic lung disease (1), heart failure (1). The case fatality was 9%. A possible source of exposure, such as air-conditioned rooms or evaporative condensers, was reported in 4 cases.