STX1A and hemolytic-uremic syndrome: STEC O130:H11 was invariably eae negative and stx2a positive, with 30% of isolates (10/31) also carrying stx1a. It was the 14th most common serotype amongst all STEC cases (31 cases, 1%) but was disproportionately associated with HUS (three cases, 3%) (Figure 6).