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Genomic analysis of azithromycin-resistant Salmonella from food animals at slaughter and processing, and retail meats, 2011-2021, United States.

ABSTRACT:

Importance

Macrolides of different ring sizes are critically important antimicrobials for human medicine and veterinary medicine, though the widely used 15-membered ring azithromycin in humans is not approved for use in veterinary medicine. We document here the emergence of azithromycin-resistant Salmonella among the NARMS culture collections between 2011 and 2021 in food animals and retail meats, some with co-resistance to ceftriaxone or decreased susceptibility to ciprofloxacin. We also provide insights into the underlying genetic mechanisms and genomic contexts, including the first report of a novel combination of azithromycin resistance determinants and the characterization of multidrug-resistant plasmids. Further, we highlight the emergence of a multidrug-resistant Salmonella Newport clone in food animals (mainly cattle) with both azithromycin resistance and decreased susceptibility to ciprofloxacin. These findings contribute to a better understating of azithromycin resistance mechanisms in Salmonella and warrant further investigations on the drivers behind the emergence of resistant clones.

SUBMITTER: Ge B

PROVIDER: S-EPMC10783062 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Genomic analysis of azithromycin-resistant <i>Salmonella</i> from food animals at slaughter and processing, and retail meats, 2011-2021, United States.

Ge Beilei B Mukherjee Sampa S Li Cong C Harrison Lucas B LB Hsu Chih-Hao C-H Tran Thu-Thuy T-T Whichard Jean M JM Dessai Uday U Singh Ruby R Gilbert Jeffrey M JM Strain Errol A EA McDermott Patrick F PF Zhao Shaohua S

Microbiology spectrum 20231122 1

<h4>Importance</h4>Macrolides of different ring sizes are critically important antimicrobials for human medicine and veterinary medicine, though the widely used 15-membered ring azithromycin in humans is not approved for use in veterinary medicine. We document here the emergence of azithromycin-resistant <i>Salmonella</i> among the NARMS culture collections between 2011 and 2021 in food animals and retail meats, some with co-resistance to ceftriaxone or decreased susceptibility to ciprofloxacin. ...[more]

PMID: 37991374

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