(a) Determination of antigenic relatedness among the five newly isolated V. cholerae O139 phages by ELISA. Anti-MAD-5 phage antiserum was used as the antibody, and five V. cholerae O139 phages along with E1 Tor phage D-10 were used as antigens (□, MAD-5; ×, VE-2; ■, CAL-3; ●, S-2; ○, MS-3; •, D-10). (b) Determination of antigenic relatedness among the five newly isolated V. cholerae O139 phages by ELISA. Anti-VE-2 antisera was used as the antibody, and five V. cholerae O139 phages along with E1 Tor phage D-10 were used as antigens (□, VE-2; ×, MAD-5; ●, CAL-3; ■, S-2; ○, MS-3; •, D-10).