Page 377 - TBE_Book_V2_2019

Chapter 12b

TBE in Russia

Vladimir Igorevich Zlobin, Maria Esyunina
and Maria Syrochkina

History and Current Situation
Tick-borne viral encephalitis (tick-borne TBE case definition includes:
encephalitis, TBE) was first revealed in the Far-
East Taiga Forest in the Soviet Union in the 1) epidemiological history of tick bite or living
1
springs and summers between 1933-1935 in endemic area (without clear duration
and it was further investigated as of 1937 at a definition) or consumption of raw
large multidisciplinary expedition led by Lev (unpasteurized) goat or cow milk;
Zilber, Head of the Moscow Medical Virology 2) seasonality (spring-summer-early
2,3
Laboratory. The expedition demonstrated autumn);
that the disease develops in humans after a 3) fever that is not controlled by NSAID;
4
tick bite, the “Taiga Tick” I. persulcatus was 4) headache, clinical neurological symptoms
established as the virus carrier and the viral
etiology of the disease was confirmed by the of meningitis or encephalitis;
first isolation of the TBE virus (TBEV) in cell 5) laboratory confirmation (ELISA) IgM
culture. The clinical disease spectrum in positivity coefficient by optical density
humans and the respective pathology were (ratio with the control sample over 1 is
described and the effectiveness of immuno- considered positive) or titers; IgG titers 4-
globulin-therapy was shown. 5, 6, 7 fold increase in paired serum (10-14 days
interval); PCR of SF (not obligatory).
The Siberian subtype of the TBEV dominates in
the Russian Federation (>60% of TBEV Virological confirmation of the causative agent
isolates) as demonstrated by numerous viro- is performed in ticks only – ELISA or multiplex
8,9
logical studies. PCR for TBE virus, borreliosis, anaplasmosis.
Official registrations of TBE cases in the USSR
Only two species of ticks are epidemiologically started in 1944. Over time, two disease
14
significant for TBE in Russia: Ixodes peaks were observed (Figure 1). In the mid-
persulcatus in the Asian part and some 1950s over 5,000 cases were reported with
additional areas in the European part
further gradual decreasing of the incidence
(Yaroslavl, Sverdlovsk, Omsk, Irkutsk, until 1970. This was explained by human
Primorsky regions) and Ixodes ricinus in the expansion into natural TBE foci as well as by
European part.
considerable progress in laboratory and
clinical diagnosis of this infection. In the
There is one less epidemiologically-significant
following 7 years, 1965–1971, morbidity
species - Dermacentor pictus – confirmed as a
carrier of the TBEV in Udmurtia. 10-15 decreased year by year mainly due to large-
scale unspecific measures to prevent TBE
infection. From 1972 to 1991, however,
morbidity increased again to the level

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