Page 320 - TBE_Book_V2_2019

Chapter 12b

TBE in Kazakhstan

Andrey Dmitrovskiy

History and Current Situation

The first isolation of the TBEV in Kazakhstan In particular, for several years, they examined
was achieved in the Almaty region by M.P. birds for TBEV antibodies in Eastern
Chumakov in 1941 (only one strain from Kazakhstan using a Hemagglutination
patient) during the expedition organized by Inhibition Assay). In 1961, during the
the Central Institute of Epidemiology and examination of the sera of 46 birds, anti-TBEV
Microbiology (Moscow). This is prove that the antibodies were found in in 4 local (non-
clinically well-described “spring-summer migratory) species of birds (including Jackdaw
encephalitis” in the Almaty region was in fact and Starling). In 1962, 2 Starlings out of 260
TBE. Later in 1943, 1944 and 1945 the TBEV were also found with antibodies to the TBEV,
was also isolated from additional patients by whereas testing of 174 farm animal sera
local scientists from the Institute of turned out to be negative. At the same time,
Epidemiology and Microbiology, Laboratory of studies of humans in Eastern Kazakhstan
Virology in Alma-Ata by Prof. E. I. demonstrated seropositivity rates between
6
Demikhovsky. Isolation had been accom- 1.9 to 19.4%.
plished from CSF samples up to 8 days of
1
illness and also from brain tissue on day 12. The study of human sera in different endemic
regions showed that in mountain foci where I.
In Kazakhstan, the clinical manifestations of persulcatus is common antibodies were detect-
TBE were first described by Steblov E.M, again ed in 12.0% where in steppe foci it was 4.7%.
in the Alamty region, and the disease had At the age of 11-15 years, antibodies were
been named “Almaty encephalitis”. More- detected in 0.7%, at 16-25 years in 7.8%, at 26
over, Steblow described a chronic variant of -35 years in 9.9% and in persons over 35 years
2
8
TBE as “Kojevnikov’s Epilepsy”. In 1954 the in 8.3%.
TBEV was isolated from ticks Ixodes
3
persulcatus. The endemic zone in Eastern When studying human TBEV infection by
Kazakhstan was first characterized by different genera of ticks in different endemic
4
Zhumatov in 1957. territories of Kazakhstan, researchers conclud-
ed that in those places with no I. persulcatus
In 1959 a total of 5 TBEV strains were isolated ticks patients were infected by D. pictus or
from 315 Dermacentor pictus ticks (in 11 Dermacentor marginatus and such infections
7
pools; 45%) in Zailiysky Alatau and 12 did not result in any symptoms of TBE.
additional strains in Jungarsky Alatau (720
5
ticks – 12 pools – 100%). In the 1960s the All this work resulted in the creation of an
Arbovirus Infections Laboratory of the epidemiological surveillance network for TBE,
Institute of Epidemiology, Microbiology and including annual collection and study of ticks
Hygiene (Alma-Ata) under the direction of for infection rate, tick treatment of farm and
Prof. Zhumatov conducted extensive work to domestic animals, as well as in areas where
study the natural foci of TBE in Kazakhstan. humans concentrate and in addition vac-
cination of the population in endemic areas.

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