In the 1970s a live attenuate LGTV-based vaccine against tick-borne encephalitis was made. At the same time, another vaccine was tested, but the group vaccinated with the LGTV-based vaccine had the lowest level of developing infection decease. However, there were two big problems: the high level incidents of encephalitis (1:10 000) and not absolute protection from infection in endemic regions.
^Shapoval AN, Kamalov II, Denisova EIu, Sokolova ED, Luzin PM, Shamarina AG, Gusmanova AG, Pinaeva NI (1989). "Study of the distant consequences of immunizing people with a live vaccine against tick-borne encephalitis". Tr Inst Im Pastera (in Russian) 65: 133–5. PMID2629181.