Studies on intratypic variants of coxsackie B 1 virus

Summary

Six virus isolates recovered from clinical material and producing in inoculated infant mice histopathological changes resembling those produced by coxsackie B viruses were investigated. On the basis of cross neutralization tests all six isolates were found to be antigenically interrelated but distinct from all existing enteroviruses, including Public Health Laboratory (PHL) prototype coxsackie B 1 strain. All six isolates, however, were neutralized by the WHO reference antiserum to coxsackie B 1, Conn-5 strain, although the antisera to these isolates failed to neutralize Conn-5 strain. Conventional and kinetic neutralization tests revealed a considerable degree of antigenic heterogeneity among these isolates as well as antigenic difference between the two prototype strains, PHL and Conn-5. In the light of current definition, these six isolates, because of their narrower antigenic spectrum, as compared to prototype Conn-5 strain, cannot be considered as prime strains of coxsackie B 1 virus. The present study emphasizes the need for reexamination of present definition of “prime” and “prototype” strains. The findings also indicate the importance of using the enterovirus strains with the broadest antigenic spectrum in identification work.