title: Characterization of Antimicrobial Resistance of Listeria monocytogenes Strains Isolated from a Pork Processing Plant and Its Respective Meat Markets in Southern China.
abstract: A total of 78 Listeria monocytogenes isolates from a pork processing plant and the respective meat markets in southern China were examined. This number includes 60 isolates from pork at markets, 5 from cooked pork products at markets, 10 from pork at a processing plant, and 3 from food-contact surfaces at the processing plant. All isolates were subjected to serotyping, antimicrobial susceptibility testing, pulsed-field gel electrophoresis (PFGE), and molecular basis of antibiotic resistance. Four serogroups were identified among the 78 tested isolates, with serogroup I (serotypes: 1/2a and 3a) being predominant (42.3%, 33/78). Antimicrobial resistance was most frequently observed for tetracycline (20.5%, 16/78), streptomycin (9.0%, 7/78), cefotaxime (7.7%, 6/78), and gentamicin (6.4%, 5/78). Multiple resistances occurred among 10.2% (8/78) isolates. All strains were sensitive to ampicillin, ampicillin/sulbactam, imipenem, ciprofloxacin, levofloxacin, trimethoprim/sulfamethoxazole, and vancomycin. Two isolates were resistant to five antimicrobials. Twelve strains carried tet(M) and located on Tn916. PFGE analysis revealed genetic heterogeneity among individual serotypes. Two predominant PFGE types were found persistent from the processing plant to markets indicating that these two types of isolates were able to survive under environmental adverse conditions from the processing plant to markets, which need to be monitored. Compared to samples from the pork processing plant, the prevalence of L. monocytogenes in meat market samples tended to be higher, serovar was more variable, and the antibiotic resistance range was wider, probably due to secondary contamination. Therefore, stringent hygiene measures and bacteriological controls should be observed to reduce the risk of transmission of L. monocytogenes from food to humans.
authors.affiliation: 1 College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong, China .|2 Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen , Frederiksberg C, Denmark .
authors.forename: Lili
authors.initials: L
authors.lastname: Li
authors.affiliation: 2 Department of Veterinary Disease Biology, Faculty of Health and Medical Sciences, University of Copenhagen , Frederiksberg C, Denmark .
authors.forename: Rikke Heidemann
authors.initials: RH
authors.lastname: Olsen
authors.affiliation: 1 College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong, China .|3 Research Institute of Food Safety and Nutrition, Jinan University , Guangzhou, China .
authors.forename: Lei
authors.initials: L
authors.lastname: Ye
authors.affiliation: 1 College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong, China .
authors.forename: Wenyan
authors.initials: W
authors.lastname: Wang
authors.affiliation: 1 College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong, China .|4 State Key Laboratory of Food Safety Technology for Meat Products and Synergetic Innovation Center of Food Safety and Nutrition , Xiamen Yinxiang Group Co., Ltd., Xiamen, China .
authors.forename: Lei
authors.initials: L
authors.lastname: Shi
authors.affiliation: 1 College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong, China .|4 State Key Laboratory of Food Safety Technology for Meat Products and Synergetic Innovation Center of Food Safety and Nutrition , Xiamen Yinxiang Group Co., Ltd., Xiamen, China .
authors.forename: He
authors.initials: H
authors.lastname: Yan
authors.affiliation: 1 College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong, China .|4 State Key Laboratory of Food Safety Technology for Meat Products and Synergetic Innovation Center of Food Safety and Nutrition , Xiamen Yinxiang Group Co., Ltd., Xiamen, China .
authors.forename: Hecheng
authors.initials: H
authors.lastname: Meng
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002681:China; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005511:Food Handling; D005516:Food Microbiology; D008089:Listeria monocytogenes / Q000187:drug effects* / Q000302:isolation & purification; D013552:Swine / Q000382:microbiology
chemical_list: D000900:Anti-Bacterial Agents