COMPARISON OF THE VIBRIOCIDAL ANTIBODY-RESPONSE IN CHOLERA DUE TO VIBRIO-CHOLERAE-O139 BENGAL WITH THE RESPONSE IN CHOLERA DUE TO VIBRIO-CHOLERAE-O1

Vibrio cholerae serogroup 0139, now considered to be the second organi sm capable of causing epidemic severe dehydrating cholera, contains a capsular polysaccharide which makes it difficult for it to be used in the conventional vibriocidal antibody assay optimized for V. cholerae 01. After modification of the procedure, which involved the use of spe cific bacterial strains, a lower bacterial inoculum, and increased amo unts of complement, the vibriocidal antibody responses to V. cholerae 0139 were measured in acute- and convalescent-phase sera from 33 V. ch olerae 0139-infected and 18 V. cholerae 01-infected patients and in si ngle serum samples from 20 healthy control subjects. The responses in these individuals to V. cholerae 01 strains were also determined. Sign ificant elevations in the homologous antibody response were found only in the convalescent-phase sera from both groups of patients with chol era. These findings may explain the basis for the lack of heterologous protection between the two serogroups of V. cholerae. Healthy control s had higher background levels of vibriocidal antibody to V. cholerae 01 than to V. cholerae 0139.