[Epidemiology of tick-borne encephalitis in Southern Germany (author's transl)].

A recently developed sensitive enzyme immunoassay for the detection of IgM antibodies to tick-borne encephalitis (TBE) virus was used to reinvestigate sera of patients with the clinical diagnosis of meningitis or encephalitis but without conclusive results in the complement fixation assay for TBE virus. 62 cases with sera positive for IgM antibodies to TBE virus collected from 1976 to 1980 were evaluated with regard to clinical and epidemiological aspects of the disease. Of the 62 cases, 37 had apparently been bitten by ticks. The mean age of the patients was 34 years. After a mean incubation period of 12 days (6-21 days) nearly all patients had severe headache and meningitis, in most cases connected with high fever. In 4 patients (6.4%) a serious clinical picture with incomplete recovery was observed. One patient died. Infection peaks occur in July and October. The place of infection or residence was predominantly in southeast Bavaria.