Escherichia coli encoding Shiga toxin 2f as an emerging human pathogen

Escherichia coli harbouring the stx2f gene have been previously reported in pigeons. Here we demonstrate the presence of this allele in human diarrhoeagenic E. coli strains originally classified as atypical enteropathogenic E. coli (aEPEC). Thirty-two stx2f-positive E. coli serotyped as O63:H6, O128:H2, O132:H34, O145:H34, and O178:H7 were found to belong to a large number of clonal groups due to their different MLST-, PFGE- and virulence patterns. The appearance of various stx2f-positive clonal lineages among E. coli reveals emerging clinical significance. Therefore, it seems to be prudent to include stx2f into the diagnostic scope employed for laboratory investigation of enteric infections.