[Strain properties of the Aina/1448 serotype of the tick-borne encephalitis virus]

Four strains of tick-borne encephalitis (TBE) virus isolated in the Irkutsk region were shown by the agar gel diffusion and precipitation test with adsorbed sera to comprise a single antigenic group differing from members of the eastern and western TBE virus serotypes (Sophyin and 256 strains). The group includes the strains isolated during 20 years (1960 - 1980) from patients with chronic TBE form (Aina/1448 and 763 strains), from the brain of root vole (Microtus oeconomus Pall) (strain 147), and from Ix. persulcatus ticks (Irkutsk-6 strain). The clonal analysis showed the Aina/1448 strain population to be antigenically homogeneous.