Prevalence of cholera toxin genes (ctxA and zot) among non-O1/O139 Vibrio cholerae strains from Newport Bay, California

The examination of 137 non-O1/O139 Vibrio cholerae isolates from Newport Bay, California, indicated the presence of diverse genotypes and a temporal succession. Unexpectedly, the cholera toxin gene (ctxA) was found in 17% of the strains, of which one-third were also positive for the zot gene. This suggests that ctxA is prevalent in the region of nonepidemicity and is likely to have an environmental origin.