Page 378 - TBE_Book_V2_2019

Chapter 12b: TBE in Russia

recorded in 1964, because vector population European part of Russia (Republic of Karelia
control had been canceled. Since 1992, a (7.6), Kirov (6.6), Vologda (4.5), Kostroma
number of socioeconomic factors, including (4.0), Arkhangelsk (3.6) and Novgorod regions
large-scale allotment of land for garden plots (3.2)); and 3 regions in the Asian part (Altai
and the growing popularity of outdoor (5.9), Zabaikalsky (5.6) and Primorsky (5.3)
activities have entailed a high risk of tick bites regions). In 28 regions low incidence rates
for the urban population. As a result, the were registered (25 regions in the European
indices of TBE morbidity reached the highest part and 3 in the Asian part of Russia)
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values ever recorded. TBE peaked in 1996
and 1999 with incidence rates in these years In 2007-2016 the incidence has been 1.9±0.04
around 7.0 per 100,000 persons, resulting in per 100,000 with 27 351 TBE cases registered
more than 10,000 cases per year in the in these 10 years. The most intensive epidemic
country. process occurred in the Asian endemic areas.
High incidence rates in the European part of
The registered frequency of tick bites the RF were registered in the Kirov region
remained constant over time (1944-2016) and (8.8%). In the Asian part a cluster was formed
is at the level of 400,000-550,000 per year. In between bordering regions of Altai (16.7),
2018 there were 518,510 visits (in 2016 - Krasnoyarsk (16.2), Tomsk (16.2), Khakassia
482,059 visits; in 2017 - 509,323 visits ) to (10.6) and Tuva (10.6). Moderate incidence
medical centers due to a tick-bite with ~25% rates were established in 6 regions in the
of the cases occurring in children. 16,23,24,25 European part and 8 regions in the Asian part,
low incidence in 23 regions (Figure 1, B.). In
In two periods (1997-2006 and 2007-2016) all summary, the incidence of TBE in the RF has
Russian Federation (RF) endemic regions were significantly decreased over the past decade in
divided into three groups with an either low all regions except in Kirov, where an incidence
(≤2.9 per 100 000 population), moderate (3.0- increase from 6.6 ± 0.7 per 100,000 in 1997-
8.4 per 100 000) or high (≥8.5 per 100 000) 2006 to 8.8 ± 0.8 per 100,000 in 2007-2016
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TBE incidence (Figure 2A and B). was observed. In 2018 there were registered
1,692 cases of TBE (1.2 per 100,000), in 2017 -
Between 1997 and 2006 the average TBE 1934 cases (1.3 per 100,000), in 2016 - 2035
incidence in Russia was 4.0 ± 0.05 per 100 000
cases (1.4 per 100,000). There is a tendency of
totaling 58 585 cases in 55 regions of Russia. the TBE incidence reduction in the Russian
At that time the number of regions known to Federation. In 2012–2017 209 people died
be endemic for the disease grew progressively from TBE. 24,25
from 41 in 1997 to 47 in 2001 and 2003. The
group of regions with a high incidence per Vaccines against TBE have been available in
100,000 population included 15 regions, Russia since 1939. Already in 1938 Kagan and
where total of 48,166 (82.2%) of TBE cases co-workers developed the first “brain”
were registered: Tomsk (40.2), Krasnoyarsk formalin-inactivated vaccine from Far East
(32.6), Udmurt Republic (28.8), Altai (27.0), TBEV subtype “Sof’in” (First generation of
Khakassia (26.4), Tuva (23.0), Irkutsk (20.9), vaccines). 17,18 Vaccine effectiveness was
Kurgan (16.8), Tyumen (15.9), Buryatia (15.3), established at the level of 98%, but it induced
Perm (13.8), Kemerovo (11.6), Sverdlovsk a high level of reactogenicity and also
region (11.0), Novosibirsk (10.8) and frequently serious adverse events. A live
Chelyabinsk (8.6). Nine regions were included attenuated vaccine based on the Elantsev
into the moderate incidence group with 6,482 strain was developed but not licensed due to
registered cases (11.1%), i.e. six regions in the severe complications in the vaccinated

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