Virulence mechanisms associated with clinical isolates of non-O1 Vibrio cholerae

Twenty one isolates of non-O1 V. cholerae from patients with diarrheal illness were examined for the presence of potential virulence mechanisms. The motile strains (90%) produced cell-associated mannose-sensitive hemagglutinins which reacted with human group O, chicken, sheep and rabbit erythrocytes. Motile isolates also attached to embryonic intestinal epithelial cells (ATCC 407), and the adherence was not inhibited by the presence of 1% D-mannose. All vibrio isolates hemolyzed sheep erythrocytes. Three vibrio isolates (14%) harbored two or three plasmids which ranged in size between 1.7 and 5.2 megadaltons. The presence of the plasmid did not correlate with the presence of hemolysin, hemagglutinins, adhesions or antibiotic resistance in any of the isolates. Thus, it appears that multiple factors associated with bacterial cell surfaces influence adhesin and apparently pathogenic potential of the non-O1 vibrio isolates in the host intestine.