title: Comparison of effects of antimicrobial interventions on multidrug-resistant Salmonella, susceptible Salmonella, and Escherichia coli O157:H7.
abstract: Several strains of Salmonella have been identified as resistant to multiple antibiotics. What is not known is whether strains possessing multidrug resistance properties also have the ability to resist the killing effects of the antimicrobial interventions used in beef processing. The research project described herein was designed to determine whether antimicrobial interventions currently in place in beef processing facilities are adequate for reducing the foodborne pathogen loads on beef carcass surfaces contaminated with multidrug-resistant (MDR) Salmonella. The data presented here indicate that MDR Salmonella is reduced at least as effectively as are Escherichia coli O157:H7 and susceptible Salmonella when treated with antimicrobial interventions currently in use at most U.S. beef processing plants. The E. coli O157:H7 strains used in this study were divided into two groups, strains that have a genetic polymorphism associated with human disease and strains not typically found to cause human disease. No differences were detected in the abilities of these two strain types to survive antimicrobial interventions. These results indicate that neither the drug resistance status of a particular Salmonella strain nor the likelihood that a particular E. coli O157:H7 strain will cause human illness influences the antimicrobial efficacy of the interventions utilized by the modern beef processing plants.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, Nebraska 68933-0166, USA. terrance.arthur@ars.usda.gov
authors.forename: Terrance M
authors.initials: TM
authors.lastname: Arthur
authors.forename: Norasak
authors.initials: N
authors.lastname: Kalchayanand
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Bosilevac
authors.forename: Dayna M
authors.initials: DM
authors.lastname: Brichta-Harhay
authors.forename: Steven D
authors.initials: SD
authors.lastname: Shackelford
authors.forename: James L
authors.initials: JL
authors.lastname: Bono
authors.forename: Tommy L
authors.initials: TL
authors.lastname: Wheeler
authors.forename: Mohammad
authors.initials: M
authors.lastname: Koohmaraie
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002417:Cattle; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D024901:Drug Resistance, Multiple, Bacterial; D019453:Escherichia coli O157 / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity; D005506:Food Contamination / Q000032:analysis* / Q000517:prevention & control; D005516:Food Microbiology; D006801:Humans; D008460:Meat / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D012475:Salmonella / Q000187:drug effects* / Q000254:growth & development / Q000472:pathogenicity
chemical_list: D000900:Anti-Bacterial Agents