Prevalence of subtilase cytotoxin in verocytotoxin-producing Escherichia coli isolated from humans and raw meats in Belgium

Recently, subtilase cytotoxin (SubAB) was detected in verocytotoxin-producing Escherichia coli (VTEC) that do not carry the Locus of Enterocyte Effacement (LEE) pathogenicity island. The distribution of the subA gene in VTEC isolated from patients with the hemolytic uremic syndrome, patients with diarrheal disease and raw meats from ruminants and wildlife in Belgium was investigated with PCR. The subA gene was detected more frequently (χ ² = 10.2; d.f. = 1; P = 0.001) in VTEC from raw meats (10 of 87 strains) than in those from humans (8 of 274 strains), and never in serogroups O157, O26, O103, O111 and O145. This virulence marker could play a role in the development of HUS after infection with LEE-negative VTEC but was only found in one O178:H19 isolate out of 36 HUS-associated VTEC strains.