Occurrence of phages infecting Escherichia coli O157 : H7 carrying the Stx2 gene in sewage from different countries

Shiga toxin-converting bacteriophages are involved in the pathogenicity of some enteric bacteria, such as Escherichia coli O157:H7. Recent studies hav e demonstrated a relatively high presence of Shiga toxin 2 phages in sewage from Spain, but no data on sewage from other areas were available. In orde r to evaluate the presence of such phages in sewage from diverse geographic al origins, 33 sewage samples, including samples from eight different Europ ean countries as well as from New Zealand and South Africa were analysed. U sing an experimental approach based on the detection of Stx 2 gene by a pha ge enrichment culture followed by PCR, bacteriophages infecting E. coli O15 7:H7 carrying the Shiga toxin 2 gene were detected in 15 of the samples stu died. Results presented here show that the presence of phages carrying the Stx 2 gene is common in sewage from developed countries. (C) 2000 Federatio n of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.