[A comparative experimental study of pathogenic properties of new strains of California encephalitis virus serogroups].

Experiments in noninbred mice, Syrian hamsters and grey monkeys were made to characterize the pathogenic properties of new strain of the California encephalitis serogroup isolated for the first time on the island of Taimir, in the Murmansk, Leningrad, Tver regions and in Karelia. All the strains displayed marked tropism for the CNS. The strains isolated in the northern regions of this country turned out more pathogenic for the animals. The strain Leiv-12812 Kl (isolated in the Tver region) differed from the remaining ones in more pronounced pathogenicity for the monkeys, as well as in the site and intensity of brain lesions. The persistence of the virus in hamsters organs may play a role of a reservoir of infection in nature.