Fluoroquinolones are important antimicrobial drugs used to treat human Salmonella infections, and resistance is rare in the United States for isolates from human and animal sources. Recently, a number of Salmonella isolates from swine cecal contents and retail pork products from National Antimicrobial Resistance Monitoring System (NARMS) surveillance exhibited decreased susceptibility to ciprofloxacin. We identified two qnrB19 quinolone resistance plasmids that are predominantly responsible for this phenomenon and found them distributed among several Salmonella serotypes isolated throughout the United States.
Tyson GH, Tate HP, Zhao S, Li C, Dessai U, Simmons M, McDermott PF; Identification of Plasmid-Mediated Quinolone Resistance in Salmonella Isolated from Swine Ceca and Retail Pork Chops in the United States; Antimicrob Agents Chemother. 2017 Sep 22;61(10). pii: e01318-17. doi: 10.1128/AAC.01318-17. Print 2017 Oct. PMID: 28784677 PMCID: PMC5610501 DOI: 10.1128/AAC.01318-17
Full article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5610501/