title: Detection of sul1, sul2 and sul3 in sulphonamide resistant Escherichia coli isolates obtained from healthy humans, pork and pigs in Denmark.
abstract: The occurrence of sulphonamide resistance was investigated in 998 Escherichia coli isolates, obtained from pig faeces collected at slaughter, Danish pork collected at retail outlets and from faeces from healthy persons in Denmark. In total 18% (n=35), 20% (n=38) and 26% (n=161) of the E. coli isolates obtained from humans, pork and pigs, respectively, were resistant to sulphonamide. All sulphonamide resistant E. coli isolates were investigated for the presence of sul1, sul2, sul3 and intI1 genes by PCR. The sul1 gene was detected in 40% (n=14), 29% (n=11) and 55% (n=88) of the sulphonamide resistant isolates from humans, pork and pigs, respectively. The sul2 gene was detected in 80% (n=28), 76% (n=29) and 50% (n=81) of isolates from humans, pork and pigs, respectively. None of the human isolates were PCR-positive for sul3, whereas sul3 was present in 5% of the pork isolates and 11% of the pig isolates. Of the 113 sul1 positive isolates, 97 carried the integron-associated integrase gene intI1. All 20 sul3 positive isolates were positive for intI1, and in 12 of these isolates sul3 was the only sulphonamide resistance gene detected. The origin of sul1 and sul2 found in isolates from healthy humans is speculative, but their spread from pigs to humans via the food chain is possible.
authors.affiliation: National Center for Antimicrobials and Infection Control, Statens Serum Institut, Artillerivej 5, DK-2300 Copenhagen S, Denmark. ama@ssi.dk
authors.forename: Anette M
authors.initials: AM
authors.lastname: Hammerum
authors.forename: Dorthe
authors.initials: D
authors.lastname: Sandvang
authors.forename: Sigrid R
authors.initials: SR
authors.lastname: Andersen
authors.forename: Anne Mette
authors.initials: AM
authors.lastname: Seyfarth
authors.forename: Lone Jannok
authors.initials: LJ
authors.lastname: Porsbo
authors.forename: Niels
authors.initials: N
authors.lastname: Frimodt-Møller
authors.forename: Ole E
authors.initials: OE
authors.lastname: Heuer
mesh_terms: D000003:Abattoirs; D000818:Animals; D003718:Denmark; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology*; D006801:Humans; D032023:Integrons; D008460:Meat / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D013449:Sulfonamides / Q000494:pharmacology*; D013552:Swine / Q000382:microbiology
chemical_list: D029968:Escherichia coli Proteins; C091882:Sul1 protein, E coli; D013449:Sulfonamides