Virulence properties of rough and smooth strains of Vibrio cholerae O1.

A comparative study was carried out to see the differences in pathogenicity of rough and smooth strains. A total of 10 strains including 5 each of rough and smooth strains of Vibrio cholerae O1 were tested and found positive for toxin production by enzyme-linked immunosorbent assay (ELISA) in Richardson's and AKI media. All the smooth and rough strains, except one, showed a titre of 1: 10 and 1: 100 in Richardson's and AKI media, respectively. Both types of strains produced enterotoxin in rabbit ileal loop (RIL). The differences in multiplication abilities of smooth and rough strains in RIL were statistically significant (P <0.05). However, these differences in multiplying abilities did not influence the adherence potential or enterotoxin production as there was no significant difference (P >0.05) between these properties. This study demonstrated that the rough strains are equally pathogenic and as important as smooth strains.