Variations in Coxsackie virus pathogenicity in the course of routine isolations in suckling mice and cell cultures

From 1961 to 1973 416 Coxsackie viruses were isolated, most of the isolations (303) being done in the last 5 years. Most of the isolates belong to a group A, with a predominance of types A6 and A8. Many variations were observed in strains belonging to the same type, as concerns their isolation in human embryo cell cultures and suckling mice; many Coxsackie A5, A6 and A8 strains showed a low pathogenicity for these animals.