Our **data** shows that only 7/93 strains are divergent in these genes and this includes the two PCR-ribotype 017 strains discussed above, two non-toxigenic strains and two PCR-ribotype 078 strains. PCR-ribotype 078 strains have previously been reported to be non-motile [32] and although the CD630 flagella loci appears to be highly divergent or absent in these stains, the corresponding R20291 flagella and flagella glycosylation genes are present, indicating that another mechanism of variation is responsible for their non-motility.