Comparative studies of several vaccinia virus strains by intrathalamic inoculation into cynomolgus monkeys.

From the comparative studies of the virulence of several vaccinia virus strains by intrathalamic inoculation into cynomolgus monkeys, the following results were observed. The CV1 virus was most virulent, the New York City Board of Health, Ikeda, EM63, and Lister viruses were slightly less virulent, and DIs and LC 16 viruses least virulent.