Serological studies in El tor cholera

ABSTRACT

Three test were utilized, namely agglutination, vibriocidal and the hemolysis-inhibition tests in determining the serological responses of 161 immunized individuals in this study. Three vaccines were given in different dosage regimen - El Tor, mixed El tor and cholera , and classical cholera vaccines. Higher agglutinative and vibriocidal antibody titers were obtained among those immunized with two or three doses of El Tor vaccine than with the other two types of vaccines. The agglutinating antibody response to classical Inaba and Ogawa challenge by those given the El tor vaccine was even higher than those that received classical cholera vaccine. Antibodies to both classical and El Tor strains of cholera vaccine but to a lesser degree than by either the pure El Tor or the mixed vaccine. These differences in percentage with rise in agglutinative titer were found significant by statistical analysisIt was further obseved that the reduction in vibriocidal antibody titer was not as marked as in the agglutinative antibody titer 6 months after primary immunization. It is of special interest and utmost importance to note that the usual single 1 cc. adult dose given as a booster 6 months after the primary immunization failed to produce sufficient agglutinative antibodies and on this basis it is felt that the double regimen should instead be preferred. (Summary)