In the present investigation, a comparatively high occurrence of stx2 virulence gene (48.3%) was found as compared to stx1 (39.1%) and this is a cause of concern as epidemiological studies showed that E. coli possessing stx2 is more virulent (associated with HUS) as compared to stx1 [6, 54]. This evidence concerns the gene STX2 and hemolytic-uremic syndrome.