title: Antimicrobial resistance of Listeria monocytogenes and Listeria innocua from meat products and meat-processing environment.
abstract: A total of 336 Listeria isolates from ready-to-eat (RTE) meat products and meat-processing environments, consisting of 206 Listeria monocytogenes, and 130 Listeria innocua isolates, were characterized by disc diffusion assay and minimum inhibitory concentration (MIC) values for antimicrobial susceptibility against twenty antimicrobials. Resistance to one or two antimicrobials was observed in 71 L. monocytogenes isolates (34.5%), and 56 L. innocua isolates (43.1%). Multidrug resistance was identified in 24 Listeria isolates, 18 belonging to L. innocua (13.9%) and 6 to L. monocytogenes (2.9%). Oxacillin resistance was the most common resistance phenotype and was identified in 100% Listeria isolates. A medium prevalence of resistance to clindamycin (39.3% isolates) and low incidence of resistance to tetracycline (3.9% isolates) were also detected. Listeria isolates from RTE meat products displayed higher overall antimicrobial resistance (31.3%) than those from the environment (13.4%). All the strains assayed were sensitive to the preferred antibiotics used to treat listeriosis. Results showed that although antimicrobial resistance in L. monocytogenes still occurs at a low prevalence, L. innocua can form a reservoir of resistance genes which may transfer between bacterial species, including transference to organisms capable of causing disease in humans.
authors.affiliation: Department of Animal Production and Food Science, Veterinary Faculty, University of Zaragoza, c/Miguel Servet 177, 50013 Zaragoza, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Gómez
authors.affiliation: Department of Animal Production and Food Science, Veterinary Faculty, University of Zaragoza, c/Miguel Servet 177, 50013 Zaragoza, Spain.
authors.forename: Ester
authors.initials: E
authors.lastname: Azón
authors.affiliation: Department of Animal Production and Food Science, Veterinary Faculty, University of Zaragoza, c/Miguel Servet 177, 50013 Zaragoza, Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: Marco
authors.affiliation: Department of Animal Production and Food Science, Veterinary Faculty, University of Zaragoza, c/Miguel Servet 177, 50013 Zaragoza, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Carramiñana
authors.affiliation: Department of Animal Production and Food Science, Veterinary Faculty, University of Zaragoza, c/Miguel Servet 177, 50013 Zaragoza, Spain.
authors.forename: Carmina
authors.initials: C
authors.lastname: Rota
authors.affiliation: Department of Animal Production and Food Science, Veterinary Faculty, University of Zaragoza, c/Miguel Servet 177, 50013 Zaragoza, Spain. Electronic address: aarino@unizar.es.
authors.forename: Agustín
authors.initials: A
authors.lastname: Ariño
authors.affiliation: Department of Animal Production and Food Science, Veterinary Faculty, University of Zaragoza, c/Miguel Servet 177, 50013 Zaragoza, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Yangüela
mesh_terms: D000003:Abattoirs; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D005506:Food Contamination / Q000032:analysis; D005511:Food Handling / Q000295:instrumentation*; D008087:Listeria / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D008089:Listeria monocytogenes / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D008461:Meat Products / Q000382:microbiology*; D008826:Microbial Sensitivity Tests
chemical_list: D000900:Anti-Bacterial Agents
keywords: Antimicrobial resistance; Listeria innocua; Listeria monocytogenes; Processing environment; Ready-to-eat meat products