The prevalence of tick-borne encephalitis in the region of West Bohemia (Czech Republic) between 1960–2005

Abstract

Between 1960-2005, 1,621 cases of tick-borne encephalitis were confirmed by laboratory testing in the region of West Bohemia (now the regions of Pilsen and Karlovy Vary) which represents a rate of infection of 4.1 per 100,000 inhabitants per year. The highest infection rate was established in men aged 20-24 and women aged 45-54. Over the monitored years, there was a significant shift of the maximum infection rate into an older age group. Currently, it is the 45-64 age group which carries the highest rate of infection. Of the identified disease cases, 12 were lethal, which represents 0.7% of the total. Over the years, the risks of transmission in particular areas of the region have changed. The highest infection rate is currently in the district of Klatovy (21.7 per 100,000 inhabitants per year). Of the total number, only two cases were contracted outside the Czech Republic (Slovakia and Austria). In 4.8% cases, the patient's anamnesis showed data on the consumption of non-pasteurized milk. 3.0% of infections probably originated as a result of professional exposure. Over the years, the season of infection has extended. Presently, the transmission can occur anytime between March and November. According to official data, only 6.7% of the population in the Pilsen district has been vaccinated so far. The low percentage of vaccinated cases may, however, in no way influence the unfavorable epidemiological situation regarding tick-borne encephalitis.

Variable spikes in tick-borne encephalitis incidence in 2006 independent of variable tick abundance but related to weather

“…In SE Czechland (Brno-mesto district, Jihomoravský administrative region) (Figure 6d ) and also the northeast (Bruntal district, Moravskoslezský region – data not shown), the seasonal peak in TBE incidence typically occurs in August, one month later than the mean for Czechland as a whole [ 1 ] (pale grey bars, Figure 6d ) or for West Bohemia [ 17 ], despite the relatively early peak in tick abundance (March–May). In 2006, TBE cases were higher throughout the normal season, but there was a disproportionate increase in the autumn when ticks were at low levels.…”

History of Arbovirus Research in the Czech Republic

“…Human incidence of TBE in particular areas of the Czech lands was reported in a number of papers [196][197][198][199][200][201][202][203][204][205][206][207][208][209][210][211][212][213]. The incidence rate is relatively high in the Czech lands compared with other European countries.…”