title: Prevalence and characterization of cefotaxime and ciprofloxacin co-resistant Escherichia coli isolates in retail chicken carcasses and Ground Pork, China.
abstract: Retail meat products could serve as an important medium for the transfer of multidrug resistant isolates from food-producing animals to the community. In this study, the prevalence and characteristics of cefotaxime and ciprofloxacin co-resistant Escherichia coli isolates were investigated in retail chicken and ground pork samples from four provinces of China. The isolates were subjected to phylogenetic group typing and antimicrobial susceptibility testing. All isolates were further characterized by pulsed-field gel electrophoresis to determine the genetic relatedness. These isolates were also screened for beta-lactamase genes, quinolone resistance determinants by PCR, and followed by DNA sequence analysis. Cefotaxime and ciprofloxacin co-resistant E. coli isolates with diverse genetic origins were recovered in 31.9% (106/332) of retail meat samples. E. coli isolates of phylogenetic group A were dominant (59.4%, 63/106), and all isolates showed multidrug resistant profiles. The dominant resistant profiles were AMP-CAZ-CTX-CIP-CHL-GEN-SXT-TET (n=43) and AMP-CAZ-CTX-CIP-CHL-SXT-TET (n=43). Point mutations in quinolone resistance determination regions of topoisomerases were identified in all the isolates, and most of the isolates accumulated three (n=78) or four (n=21) point mutations. Plasmid-mediated quinolone-resistant determinants were identified in 68 isolates, including oqxAB (n=66), qnrS1 (n=7), qnrS2 (n=4), and aac(6')-Ib-cr (n=9). Eight subtypes of bla(CTX-M) were identified in 103 E. coli isolates, and blaCTX-M-55 (n=90) was dominant. This study highlights that retail meat could serve as an important reservoir of cefotaxime and ciprofloxacin co-resistant E. coli isolates. It is necessary to evaluate their contribution in the community and hospital infections.
authors: 1 Department of Food Science, National Institutes for Food and Drug Control , Beijing, People's Republic of China .
authors: Xiao
authors: X
authors: Xu
authors: Shenghui
authors: S
authors: Cui
authors: Fenglan
authors: F
authors: Zhang
authors: Yanping
authors: Y
authors: Luo
authors: Yihai
authors: Y
authors: Gu
authors: Baowei
authors: B
authors: Yang
authors: Fengqin
authors: F
authors: Li
authors: Qian
authors: Q
authors: Chen
authors: Gang
authors: G
authors: Zhou
authors: Yeru
authors: Y
authors: Wang
authors: Lu
authors: L
authors: Pang
authors: Lan
authors: L
authors: Lin
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D002439:Cefotaxime / Q000494:pharmacology; D002645:Chickens; D002681:China / Q000453:epidemiology; D002939:Ciprofloxacin / Q000494:pharmacology; D004197:Disease Reservoirs; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission*; D006801:Humans; D008461:Meat Products / Q000382:microbiology*; D010802:Phylogeny; D010957:Plasmids; D016133:Polymerase Chain Reaction; D015995:Prevalence; D013552:Swine; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D002939:Ciprofloxacin; D001618:beta-Lactamases; D002439:Cefotaxime