Industrial hog operation (IHO) workers are at increased risk of carrying
This content will become publicly available on October 20, 2023
- Brodsky, Igor E.
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- Infection and Immunity
- Sponsoring Org:
- National Science Foundation
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Comparison of livestock-associated and community-associated Staphylococcus aureus pathogenicity in a mouse model of skin and soft tissue infection
Industrial hog operation (IHO) workers are at increased risk of carrying
Staphylococcus aureusin their nares, particularly strains that are livestock-associated (LA) and multidrug-resistant. The pathogenicity of LA- S. aureusstrains remains unclear, with some prior studies suggesting reduced transmission and virulence in humans compared to community-associated methicillin-resistant (CA-MRSA) S. aureus. The objective of this study was to determine the degree to which LA- S. aureusstrains contracted by IHO workers cause disease relative to a representative CA-MRSA strain in a mouse model of skin and soft tissue infection (SSTI). Mice infected with CC398 LA- S. aureusstrains (IHW398-1 and IHW398-2) developed larger lesion sizes with higher bacterial burden than mice infected with CA-MRSA (SF8300) ( p< 0.05). The greatest lesion size and bacterial burden was seen with a CC398 strain that produced a recurrent SSTI in an IHO worker. The LA- S. aureusinfected mice had decreased IL-1β protein levels compared with CA-MRSA-infected mice ( p< 0.05), suggesting a suboptimal host response to LA- S. aureusSSTIs. WGSA revealed heterogeneity in virulence factor and antimicrobial resistance genes carried by LA- S. aureusand CA-MRSA strains. The observed pathogenicity suggest that more attention should be placed on preventing the spread of LA- S. aureusinto human populations.
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