Production and evaluation of antisera for serological type determination of group-B streptococci by double diffusion in agarose gel.

A double diffusion technique for serological typing of Group-B streptococci is presented. The method is valuable both for type determination on a large scale, as well as for evaluation of the specificity of type antisera. As in previously published methods, HC1-extracted antigens are used. The preparation of type antisera is described and the reactions of some selected sera are given in figures. The advantages of the method are good economy of antisera and easy recognition of weak and/or unspecific precipitates. The method is especially useful in epidemiological investigations.