STX1A and infection: Livestock, including cattle and sheep, are the main reservoir of diarrhoeagenic E. coli virulence factors stx1, stx2 and eae (Cookson et al. 2006; Jaros et al. 2016; Browne et al. 2018) and a suggested source for human infection either through direct contact or exposure to environments contaminated with ruminant faeces (Jaros et al. 2013).