Epidemiological Trends of Trans-Boundary Tick-Borne Encephalitis in Europe, 2000–2019

Abstract

Tick-borne encephalitis is a neuroinfection widely distributed in the Euro–Asia region. Primarily, the virus is transmitted by the bite of infected ticks. From 2000–2019, the total number of confirmed cases in Europe reported to the European Centre for Disease Prevention and Control was 51,519. The number of cases decreased in 2014 and 2015; however, since 2015, a growing number of cases have been observed, with the involvement of countries in which TBE has not been previously reported. The determinant factors for the spread of TBE are host population size, weather conditions, movement of hosts, and local regulations on the socioeconomic dynamics of the local and travelling people around the foci areas. The mean incidence rate of tick-borne encephalitis from 2000–2019 in Europe was 3.27, while the age-adjusted mean incidence rate was 2.19 per 100,000 population size. This review used several articles and data sources from the European Centre for Diseases Prevention and Control.

Fatal Case of Imported Tick-Borne Encephalitis in South Serbia

“…The case described here is in accordance with current TBE incidence trends, since the first signs of disease and nervous system involvement occurred June. It should be highlighted that tick bite in our patient occurred during forest hiking, which is a high-risk activity for TBEV exposure in endemic territories, such as Switzerland [8]. For same reason, pre-exposure immunization against TBE is recommended for travelers visiting endemic countries [3,8,9].…”

“…It should be highlighted that tick bite in our patient occurred during forest hiking, which is a high-risk activity for TBEV exposure in endemic territories, such as Switzerland [8]. For same reason, pre-exposure immunization against TBE is recommended for travelers visiting endemic countries [3,8,9]. Similar recommendation exists in Serbia, thus up to today neither of two vaccines available in Western Europe (i.e., Encepur and FSME-IMMUN) are not registered in Serbia for routine application [3].…”

“…According to phylogenetic clustering and geographical distribution, five main subtypes of TBEV are classified as Western (European, TBEV-Eu), Siberian (Eastern, TBEV-Sib), Far-Eastern (TBEV-Fe), Baikalian (TBEV-Bkl), and Himalayan (TBEV-Him). Although TBEV-Eu is dominant subtype in many European countries, other subtypes (i.e., TBEV-Sib, and TBEV-Fe) can be present in different proportions, especially in Baltic countries and the rest of East Europe [1,3,8].…”

Fatal Case of Imported Tick-Borne Encephalitis in South Serbia

“…The case described here is in accordance with current TBE incidence trends as the first signs of disease and nervous system involvement occurred in June. It should be highlighted that the tick bite in our patient occurred during forest hiking, which is a high-risk activity for TBEV exposure in endemic territories, such as Switzerland [8]. For the same reason, pre-exposure immunization against TBE is recommended for travelers visiting endemic countries [3,8,9].…”

“…According to phylogenetic clustering and geographical distribution, five main subtypes of TBEV have been classified as Western (European, TBEV-Eu), Siberian (Eastern, TBEV-Sib), Far-Eastern (TBEV-Fe), Baikalian (TBEV-Bkl) and Himalayan (TBEV-Him). Although TBEV-Eu is the dominant subtype in many European countries, other subtypes (i.e., TBEV-Sib, TBEV-Fe) have been reported in some Baltic countries and in some countries in Eastern Europe as well as Asia [1,3,8].…”