In 1960-1999 in the West Bohemian region 1216 cases of tick-borne encephalitis were recorded, four were fatal. Since 1992 there was a marked increase in the number of these infections--in 1992-1999 the relative morbidity was 6.7 per 100,000 population per year, the highest specific morbidity shifted to the age group of 55-64 years. In the whole region changes occurred as to the probable transmission of infection. By the end of 1999 in western Bohemia the hygiene service immunized, by at least three doses against tick-borne encephalitis 23,225 subjects, i.e. 2.7% of the population. The negligible vaccination rate did not have so far an impact on the epidemiological characteristics of the infection. In view of the more frequent and clinically more severe affection in elderly subjects it is important to raise the vaccination rate in particular in more advanced age groups.

History of Arbovirus Research in the Czech Republic