Two strains of Vibrio cholerae non-O1 possessing somatic (O) antigen factors in common with V. cholerae serogroup O139 synonym "Bengal"

Abstract

Two strains (O22 reference strain, 169-68, and strain 490-93 isolated from a patient with diarrhea in Thailand) ofVibrio cholerae non-O1 possessing somatic (O) antigen factors in common withV. cholerae O139 synonym Bengal are described. The O antigens of these two strains were closely related to that ofV. cholerae O139 in an a,b-a,c type of relationship, but were not completely identical with serogroup O139. Therefore, both these strains are not classified into the O139 serogroup ofV. cholerae, because they have their own major antigens. As the strain 490-93 could not be placed into any of the 154 established O serogroups ofV. cholerae, this strain was assigned to a new serogroup, O155. For practical use, the diagnostic antiserum prepared against the O139 reference strain (MO45, ATCC 51394) ofV. cholerae must be absorbed with reference strains 169-68 and 490-93 representing serogroups O22 and O155 ofV. cholerae to remove cross-reacting agglutinins of the O22 and O155 strains, respectively.