Prevalence and characterization of ciprofloxacin-resistantspp. isolated from food animals during 2010-2023 in South Korea.

Abstract

We isolated 6,561strains from food animals, cattle ( = 217), pigs (= 1526), chickens ( = 3942), and ducks ( = 876). Isolates were evaluated for antimicrobial sensitivity, mutations in quinolone resistance determination regions (QRDRs), and plasmid-mediated quinolone resistance (PMQR) genes. Clonal relationship and genetic diversity were assessed by multi-locus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Overall, 3.1% of isolates exhibited resistance to ciprofloxacin. Commonly identified mutations in QRDRs were S83F, D87N, and D87G in; T57S and S80I in; and L416F in. Furthermore, mutations differed by serotypes. InAlbany, S83F mutation inand T57S inwere prevalent, while inKentucky, S83F and D87N in, T57S and S80I in; and inIndiana, S83F and D87G in, T57S and S80R in, and L416F inwere common. Amongst PMQRs,was mainly observed inAlbany,inIndiana, andinAlbany. Among STs, ST198Kentucky was predominant, followed by ST292Albany and ST17Indiana. Of 26 pulsotypes, KX1KA1 was mainly identified inKentucky, AX1AA1 inAlbany, and IX1IA1 inIndiana. Taken together, ciprofloxacin-resistantcan pose health hazards to humans and other animals.