New foci of tick-borne encephalitis virus in Europe: consequences for travellers from abroad.

Tick-borne encephalitis (TBE) virus is endemic in many European countries. To assess the risk of infection by TBE virus, maps of TBE foci are a helpful tool for travellers. The TBE reporting system is insufficient in some countries leading to incomplete data, low awareness and underestimation of the risk of infection. In TBE endemic countries with a low vaccine coverage rate, the number of reported TBE cases is increasing and new TBE foci are emerging in a number of European countries. People living in and travellers going into such areas might be more exposed to TBE virus than estimated, based on the current epidemiological maps.