**1. Introduction**

Tick-borne encephalitis (TBE) is an important human viral infection of central nervous system (CNS) endemic in a large part of Europe and Asia. The causative agents are three different TBE virus (TBEV) subtypes named European, Siberian and Far-Eastern [1]. In spite of the pronounced genetic similarity of these flaviviruses, the illness caused by individual subtype is not entirely comparable to those caused by the other subtypes.

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The clinical course of acute illness is highly variable. Due to the relatively high proportion of severe cases and a considerable proportion of patients with long-lasting sequelae which may have a significant impact on quality of life, the disease represents high costs for healthcare system and society.

Herein we present an overview of TBE, including a short historical outline, basic information on TBEV, and of the epidemiology, pathogenesis, clinical manifestations, diagnosis and treatment of TBE, as well as on the course and outcome of the disease and its prevention.
