Pathogenicity of Coxsackie A-21 Virus for Suckling Mice

SummaryThe production of a myopathy and paralysis in mice inoculated with tissue culture passaged Coxsackie A-21 virus was directly related to the inoculum dose and extent of virus multiplication. The virus yield from paralyzed mice was usually about 1067 TCD50 or greater per mouse. Four strains of naturally occurring virus did not produce paralysis of suckling mice but virus multiplication occurred in mice with 2 of the 4 strains. Serial passage of Coxsackie A-21 virus in HEK cell cultures did not alter its virulence for suckling mice. The histopathologic changes associated with Coxsackie A-21 virus infection in mice were characterized by a waxy degeneration of the skeletal musculature which was generally confined to the lower extremities.