Studies on preparation of a tick-borne encephalitis (TBE) vaccine from the Skalica strain.

Diethylether-treated vaccine against tick-borne encephalitis (TBE) represents a new type vaccine consisting of lipid-free and antigenically efficient components instead of whole virus particles. The TBE virus strain designated Skalica was used for vaccine preparation. This strain is thermosensitive, produces small plaques under agar overlay, is nonpathogenic for adult white mice following subcutaneous (s.c.) application and causes threshold viraemia in host animals. The vaccine was harmless and immunogenic as evidenced by experiments on white mice. Antibodies to TBE virus strain Ir 13 present in human healthy population of a natural TBE focus showed similar levels when tested with the Skalica strain. The Skalica virus strain can be recommended for preparation of the vaccine against TBE.