The characteristics of the reactogenicity and immunological activity of a new cholera bivalent chemical vaccine based on the results of controlled trials

: The reactogenic properties and immunological potency of modified cholera chemical vaccine (choleragen-toxoid + O-antigens Inaba and Ogawa) were tested in 278 volunteers aged 18 years and over in comparison with those of a commercial batch of monovalent cholera vaccine (choleragen-toxoid + O-antigen Inaba). The cholera vaccine, enriched with O-antigen Ogawa, was found to be safe; vaccination with this vaccine was not accompanied by the development of systemic and local reactions whose frequency and intensity met the requirements for the reactogenic properties of commercial cholera vaccine. The immunological potency of the bivalent vaccine with respect to strain Inaba was not inferior to that of the commercial vaccine; at the same time in persons immunized with the new preparation the titers of vibriocidal antibodies to strain of serovar Inaba were five-fold higher. The conclusion on the expediency of using cholera chemical vaccine enriched with O-antigen Ogawa was made.