MOLECULAR CHARACTERIZATION OF VIBRIO-CHOLERAE O139 ISOLATES FROM ASIA

In 1992, a serologically novel clone of Vibrio cholerae, designated O1 39, caused large epidemics of diarrhea in India and Bangladesh. To det ermine the extent of the spread of V. cholerae O139 worldwide, 484 V. cholerae non-O1 strains isolated from different patients with diarrhea in Thailand, Indonesia, the Philippines, and Peru in 1993 were tested for agglutination in O139 antisera. One hundred fifty-one of these 48 4 isolates were examined for genes encoding cholera toxin, zonula occl ulans toxin, the repetitive sequence 1, and the toxin coregulated pili n A (the V. cholerae virulence gene complex). Thirty-three percent (12 2 of 364) of V. cholerae non-O1 strains isolated from different patien ts with diarrhea in Thailand agglutinated in O139 antisera. Ninety-eig ht percent (120 of 122) of V. cholerae O139 contained the V. cholerae virulence gene complex. None of the 104 V. cholerae non-Ol strains iso lated from patients with diarrhea in Indonesia or the 14 strains from patients with diarrhea in the Philippines were serotype O139. Four dif ferent ribotypes were found in V. cholerae O139 isolated in Asia. Twen ty-three (47%) of 49 Thai O139 strains examined were of different ribo types than isolates from India and Bangladesh; V. cholerae strains tha t were not O1 or O139 that were isolated from flies and water in Thail and 11 years previously in 1981 contained the same V. cholerae virulen ce gene complex found in V. cholerae O1 and O139. This suggests that o ther unidentified virulence determinants are involved in V. cholerae O 139 pathogenesis.