[Enterovirus type 71 pathogenicity for laboratory animals].

Enterovirus type 71 (E71) strains isolated from specimens of the brain and feces of children during an outbreak of poliomyelitis-like infection in Bulgaria in 1975 produce paralytic disease in newborn and adult cotton rats, newborn white mice, and monkeys. By the type of the myo- and neurotropic properties manifested in animal experiments the Bulgarian E71 strains are very close to neuropathogenic strains of Coxsackie A7, A14, and A16 viruses. The infection induced by the Bulgarian E71 strains in green monkeys was by clinical symptoms (tremor, convulsions, death), the speed of the development of the process and the type of morphological lesions particularly similar to the clinical and morphological manifestations of infection observed in most severe cases in children during the outbreak in Bulgaria. Inoculation of newborn and adult cotton rats, newborn white mice and Macaca rhesus monkeys with large doses of the prototype BrCr strain of enterovirus 71 (10(5.0)--10(6) TCD50) caused no clinically manifest disease of the animals.