[Comparative study of the immunogenicity of Shigella sonnei differing in enzyme activity and colicinogenicity].

The possibility of reproducing specific postinfectious antishigella immunity on the pulmonary model (by the intranasal infection of white mice) is shown. This method revealed that 2 compared Sh. sonnei strains, typical representatives of enzymatic types II and III with colicinogenic labels S5 and IE2 respectively, had unequal immunogenicity. Strain II S5 belonging to the most virulent type of Sh. sonnei possessed noticeably greater immunogenicity. Strain III IE2 with lesser immunogenicity was the representative of a less virulent variety of these bacteria. The results thus obtained were in complete accord with the data contained in the literature on the direct relation between the degree of virulence possessed by Sh. sonnei and their immunogenicity, as well as on the significance of the immunological factor in the epidemiology of Sh. sonnei dysentery.