A new Shiga toxin 2 variant (Stx2f) from Escherichia coli isolated from pigeons

We have isolated Shiga toxin (Stx)-producing Escherichia coli (STEC) strain s from the feces of feral pigeons which contained a new Stx2 variant gene d esignated stx(2f), This gene is most similar to sltIIva of patient E. coli O128:B12 isolate H.I.8. Stx2f reacted only weakly with commercial immunoass ays. The prevalence of STEC organisms carrying the stx(2f) gene in pigeon d roppings was 12.5%. The occurrence of a new Stx2 variant in STEC from pigeo ns enlarges the pool of Stx2 variants and raises the question whether horiz ontal gene transfer to E. coli pathogenic to humans may occur.