[Use of cross-absorbed sera in neutralization tests with viral titration by the cytopathogenic effect].

A new method for intratypic antigenic differentiation of poliovirus strains has been developed. The method is based on the use of cross-absorbed sera in neutralization tests where virus is titrated by the cytopathic effect. Qualitative differences between the antigenic structure of vaccine and "wild" strains as well as between some "wild" strains of the same serologic type have been found. The method may be used in practical laboratories.