French cattle is not a reservoir of the highly virulent enteroaggregative Shiga toxin-producing Escherichia coli of serotype O104:H4

Abstract In May–June 2011, a massive outbreak of haemolytic uraemic syndrome caused by enteroaggregative Shiga toxin (Stx)-producing Escherichia coli (STEC) O104:H4 occurred in Europe, which was linked to the consumption of sprouted seeds. As ruminants are known reservoirs of STEC, this study investigated whether cattle could be a reservoir of enteroaggregative STEC O104:H4 and a potential source of transmission to humans. A total of 1468 French cattle were analysed for faecal carriage of the outbreak strain by PCR assays targeting stx2 , wzx O104 , fliC H4 and aggR genetic markers. None of the faecal samples contained the four markers simultaneously, indicating that cattle is not a reservoir of this recently emerged E. coli pathotype.