Page 279 - TBE_Book_V2_2019

Chapter 12b

TBE in Estonia

Kuulo Kutsar

History and Current Situation
The first cases of tick-borne encephalitis (TBE) species Ixodes ricinus and Ixodes persulcatus,
in Estonia were identified in 1949. Today, are distributed throughout the country. The
Estonia is a TBE-endemic country. A TBE- high-risk infection season coincides with the
endemic area in Estonia is defined as an area period of biological activity of ticks and lasts
with circulation between ticks and vertebrate for 7 months from April to November, peaking
hosts as determined by detection of TBEV or in June–August. Most TBE cases are diagnosed
the demonstration of autochthonous infec- in persons ≥60 years of age and incidence
tions in humans or animals within the last 20 among the rural population is 1.8 times higher
years. than among the urban population.
Euro-Asian genotypes of TBEV – the Western
or European (TBEV-EU), Siberian (TBEV-Sib),

and Far-Eastern (TBEV-FE) subtypes are co-
circulating in Estonia. Vectors of TBEV, the tick

Overview of TBE in Estonia

Table 1: Virus, vector, transmission of TBE in Estonia
Co-circulation of European (TBEV-EU), Far-Eastern (TBEV-FE),
Viral subtypes, distribution
and Siberian (TBEV-Sib) subtypes

Reservoir animals Rodents, ruminants, game

Infected tick species (%) I. persulcatus 3.8%, I. ricinus on mainland 0.6%–0.8%
and on Saaremaa island 3.0% (data from 2011)

Dairy product transmission Documented but rare

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