Plasmid-mediated Quinolone Resistance among Non-TyphiSalmonella enterica Isolates, USA

Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Emerging Infectious Diseases (Impact Factor: 6.75). 11/2010; 16(11):1789-91. DOI: 10.3201/eid1611.100464
Source: PubMed


We determined the prevalence of plasmid-mediated quinolone resistance mechanisms among non-Typhi Salmonella spp. isolated from humans, food animals, and retail meat in the United States in 2007. Six isolates collected from humans harbored aac(6')Ib-cr or a qnr gene. Most prevalent was qnrS1. No animal or retail meat isolates harbored a plasmid-mediated mechanism.

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    • "Notably, it was also found in 32% of screened individuals living in a remote village in the Amazonas (Pallecchi et al., 2011). In contrast, a recent study conducted on Salmonella isolates from humans, retail meat and animals in the USA detected qnr genes in only 0.3% of human isolates, and none from animal sources (Sjolund-Karlsson et al., 2010). qnr genes are also reportedly low in China, Korea, and India (on the order of 0–3%), where aac(6 )-lb-cr is more commonly present (Menezes et al., 2010; Tamang et al., 2011b; Yu et al., 2011b; Chen et al., 2012; Kim et al., 2013). "
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