[Tick-borne encephalitis in the Russian Federation: state-of-the-art and prevention policy].

The last quarter of the 20th century in the Russian Federation was marked by an unprecedented increase in the incidence of tick-borne encephalitis (TBE) with its peaks in 1996 and 1999 when as high as 10,000 cases of the disease were notified. Its highest incidence was recorded in the Regions of the Urals and Siberia. As many as 70-80% of the persons who felt ill were urban dwellers who had been infected mainly in the anthropurgic foci occurring in abundance in the environs of cities and towns. It was found that the area of TBE had been expanded and virus-infected ticks had actively penetrated into the urban parks and small public gardens. There were as many as 70 TBE-endemic regions. As of now, it has been ascertained that TBE foci are generally combined with other infections transmitted by Ixodes ticks and caused by viruses, bacteria, rickettsia and protozoa. This result is the occurrence of mixed infections, which requires new approaches to their diagnosis, treatment, and prevention. The prevention of TBE is conventionally based on vaccination of high-risk groups comprising mainly "forest" occupations. Under the present conditions, the strategy of TBE control should be radically revised towards mass vaccination of the population living in the highly endemic areas, which will drastically reduced morbidity in the country.