[Tick-borne encephalitis in Central and Eastern Europe].

The tick-borne encephalitis virus, a major arbovirus, is endemic in Central and Eastern Europe. Since the first case of tick-borne encephalitis observed in Alsace in 1968, there have been approximately 30 cases reported in eastern France. The tick Ixodes persulcatus (and the western subtype I. ricinus) is both the main reservoir and vector of the disease. Early clinical signs of infection are followed by a second phase complicated with meningoencephalitis. The geographical distribution of the different viral subtypes would explain the variable severity of tick-borne encephalitis. Outcome may be fatal or leave major neurological sequellae. Currently, only symptomatic treatment is available, underlining the importance of prevention with anti-tick-borne virus vaccine for populations at risk living in endemic areas.