Transmission of Antimicrobial-Resistant Staphylococcus aureus Clonal Complex 9 between Pigs and Humans, United States
February 9, 2021
Pranay R Randad, Jesper Larsen, Hülya Kaya, Nora Pisanic, Carly Ordak, Lance B Price, Maliha Aziz, Maya L Nadimpalli, Sarah Rhodes, Jill R Stewart, Dave C Love, David Mohr, Meghan F Davis, Lloyd S Miller, Devon Hall, Karen C Carroll, Trish M Perl, Christopher D Heaney
Emerg Infect Dis. 2021 Mar;27(3):740-748.
PMID: 33622471 | DOI: 10.3201/eid2703.191775
Abstract
Transmission of livestock-associated Staphylococcus aureus clonal complex 9 (LA-SA CC9) between pigs raised on industrial hog operations (IHOs) and humans in the United States is poorly understood. We analyzed whole-genome sequences from 32 international S. aureus CC9 isolates and 49 LA-SA CC9 isolates from IHO pigs and humans who work on or live near IHOs in 10 pig-producing counties in North Carolina, USA. Bioinformatic analysis of sequence data from the 81 isolates demonstrated 3 major LA-SA CC9 clades. North Carolina isolates all fell within a single clade (C3). High-resolution phylogenetic analysis of C3 revealed 2 subclades of intermingled IHO pig and human isolates differing by 0-34 single-nucleotide polymorphisms. Our findings suggest that LA-SA CC9 from pigs and humans share a common source and provide evidence of transmission of antimicrobial-resistant LA-SA CC9 between IHO pigs and humans who work on or live near IHOs in North Carolina.