The aim of the study was to assess the prevalence of rickettsiosis cases in Sicily with special attention to possible occupational exposure. This research was prompted by the high number of cases reported in the press in the summer of 1999. Epidemiological data for previous years showed that Sicily was always the region where most cases of rickettsiosis occurred; we therefore examined the clinical data of patients admitted to the major infectious diseases hospital department in Palermo in the period 1996-1999. Analysis of the cases showed that an occupational risk existed (among small farmers), but that there was also an environmental risk for subjects living in rural areas due to contact with infected dogs or rural areas activities. It is therefore of fundamental importance to carry out a primary prevention programme against rickettsiosis for everyone exposed to the risk either occupationally or in leisure activities in rural areas.