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Chapter 1

A short history of TBE

Olaf Kahl, Vanda Vatslavovna Pogodina, Tatyana
Poponnikova, Jochen Süss and Vladimir Igorevich Zlobin

Key Points

• TBE virus is a flavivirus and a prominent tick-borne human pathogen occurring in parts of Asia
and Europe.
• The virus was discovered by Lev A. Zilber and co-workers in the former USSR during an
expedition in the Far Eastern taiga under the most difficult conditions in 1937.
• They and members of a second expedition under the leadership of the Academician Evgeny N.
Pavlovsky 1938 elucidated the basic eco-epidemiology of the virus.
• In their natural foci, TBE virus circulates between vectors, certain ixodid ticks, and some of their
hosts, so-called reservoir hosts, mostly small mammals.
• Five different subtypes of TBE virus have been described to date.

Introduction

Tick-borne encephalitis virus (TBEV) is an ar- gers, as the region began to develop in the
th
thropod-borne human pathogen, ecologically 19 century.
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known as an arbovirus. Taxonomically, it is a 4
member of the genus Flavivirus together with Schneider was the first to give a medical de-
other medically relevant arboviruses (e.g., scription of the ‘Epidemische akute Meningitis
Yellow fever virus, Dengue virus). The virus is serosa’ (also known as ‘Schneidersche Krank- 5
endemic in Asia and Europe where it circulates heit’ in Austria), which was in fact TBE. Panov
between its principal vectors, usually hard gave the first detailed description of the clini-
ticks of the genus Ixodes, and certain small cal picture of the so-called ‘summer encephali-
mammals, referred to as ‘reservoir hosts’, fed tis’ in the Far East.
on by virus-infected vector ticks. The bite of
infected vector ticks is also the common route This chapter presents a brief synopsis of the
of infection for humans. Each year several major milestones in TBE and TBEV research,
thousand people fall ill with TBE. Long before beginning with the discovery of the virus in
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Smith and Kilbourne discovered that ticks can the former USSR.
transmit pathogens to their hosts and before
TBEV was discovered, the disease had been Discovery of TBEV in different
mentioned in the literature. Parish records regions of Eurasia
from the Åland islands (Finland) contain case
descriptions of a disease at least similar to TBE Molecular biological data indicate that TBEV
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th
in the 18 century. ‘Taiga encephalitis’ or has its origins in Western Siberia approximate-
‘biphasic meningoencephalitis’ had been ob- ly 3100 [1800–4900] years ago. From there
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served in eastern parts of the former USSR the eastern TBEV groups spread to the east
mostly in soldiers, railway workers and log-
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