[Suspected neurological side-effects of tick-borne meningoencephalitis vaccination: experiences of the Swiss Adverse Drug Reaction Reporting Center].

The number of patients affected by tick-born encephalitis (TBE) in Switzerland has increased in the last years and an extension of the endemic foci of TBE has been observed. Therefore, active immunization by TBE vaccination has become more important. The possible adverse vaccine reactions have to be known as exactly as possible. The Swiss Drug Monitoring Center SANZ received from 1987 until June 2000 33 spontaneous cases reporting on 39 neurological adverse reactions in a close temporal relationship with a TBE vaccination and a suspected causal relationship. The following adverse reactions were reported most frequently: headache in 36%, neuropathy in 18% and meningeal irritation in 13%. Twelve out of 33 patients were hospitalized due to the adverse reaction. All neurological reactions were reversible. The spontaneous reporting scheme of the SANZ does not allow to calculate the incidence of neurological reactions after TBE vaccination. In general, adverse neurological reactions after TBE vaccination seem to be rare. According to the experiences of SANZ all reported neurological reactions were reversible.