Technological aspect of the production of live dysentery vaccines for oral administration.

An experimental technology for the production of live freeze-dried vaccines prepared from attenuated Shigella flexneri 2a and Shigella sonnei I strains was developed. It is based on the cultivation of bacterial strains in a fermentor under conditions which ensure high yields. The strains grow in S-form, their antigenic structure is preserved and they remain non-virulent. The attenuating markers are stable. The freeze-dried vaccines retain good immunogenicity when applied intra-intestinally to rats.