Antimicrobial resistance in Irish isolates of verocytotoxigenic Escherichia coli (E. coli)--VTEC.
This study compared the antimicrobial resistance profiles of Escherichia coli O157:H7 isolates (n=257) recovered from bovine hides, minced beef and human clinical samples in Ireland, to those profiles of a range of Irish non-O157 E. coli (O111 and O26) isolates (n=31) from a variety of clinical and veterinary sources. Four multi-drug resistant (MDR) E. coli O157:H7 food isolates were identified, with resistance to 10 (1 isolate), 6 (1 isolate) and 4 (2 isolates) antimicrobial agents, respectively. Two of these isolates (resistant to 7 and 4 antimicrobial classes) were characterised further by molecular methods and found to contain class 1 integrons along with a beta-lactamase-encoding tem-1 gene. Transfer of antimicrobial resistance (ampicillin, streptomycin and sulphonamides), the tem-1 gene and markers (int1, qacEDelta1, sul1) characteristic of class 1 integrons were evident in one MDR isolate (resistant to 4 antimicrobial classes) when conjugation and transformation experiments were performed. A clinical isolate and a veterinary isolate of the O111 serotype were MDR and resistant to 4 and 3 antimicrobial classes, respectively. These data suggest that the prevalence of antimicrobial resistance among the three VTEC serotypes examined in this study is low. However, these organisms may become a public health risk should they enter the food chain.
Walsh
C
C
The National Food Centre, Teagasc, Dunsinea, Ashtown, Dublin 15, Ireland.
Duffy
G
G
O'Mahony
R
R
Fanning
S
S
Blair
I S
IS
McDowell
D A
DA
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001483:Base Sequence; D002417:Cattle; D003227:Conjugation, Genetic; D003257:Consumer Product Safety; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics*; D019453:Escherichia coli O157 / Q000187:drug effects / Q000235:genetics; D005516:Food Microbiology; D006801:Humans; D032023:Integrons; D007494:Ireland; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction / Q000379:methods; D011634:Public Health; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism
D000900:Anti-Bacterial Agents; D001618:beta-Lactamases