STX1A and hemolytic-uremic syndrome: From these findings, it seems that STEC strains carrying the stx1 gene are more often confronted than those carrying stx2. Possession of OI-43/48, OI-71, and non-LEE effectors genes together with stx2, eae and a whole plasmid is the hallmark of highly virulent STEC strains that are frequently associated with outbreaks and serious diseases such as hemorrhagic colitis (HC) and HUS [8].