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Abstract The World Health Organization has declared antibiotic resistance “one of the biggest threats to global health.” Mounting evidence suggests that antibiotic use in industrial‐scale hog farming is contributing to the spread of antibiotic‐resistantStaphylococcus aureus. To capture available evidence on these risks, we searched peer‐reviewed studies published before June 2017 and conducted a meta‐analysis of these studies’ estimates of the prevalence of swine‐associated, antibiotic‐resistantS. aureusin animals, humans, and the environment. The 166 relevant studies revealed consistent evidence of livestock‐associated methicillin‐resistantS. aureus(MRSA) in hog herds (55.3%) raised with antibiotics. MRSA prevalence was also substantial in slaughterhouse pigs (30.4%), industrial hog operation workers (24.4%), and veterinarians (16.8%). The prevalence of swine‐associated, multidrug‐resistantS. aureus(MDRSA)—with resistance to three or more antibiotics—is not as well documented. Nonetheless, sufficient studies were available to estimate MDRSA pooled prevalence in conventional hog operation workers (15.0%), workers’ household members (13.0%), and community members (5.37%). Evidence also suggests that antibiotic‐resistantS. aureuscan be present in air, soil, water, and household surface samples gathered in or near high‐intensity hog operations. An important caveat is that prevalence estimates for humans reflect colonization, not active infection, and the health risks of colonization remain poorly understood. In addition, these pooled results may not represent risks in specific locations, due to wide geographic variation. Nonetheless, these results underscore the need for additional preventive action to stem the spread of antibiotic‐resistant pathogens from livestock operations and a streamlined reporting system to track this risk.
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Chemical and Biomolecular Insights into the Staphylococcus aureus Agr Quorum Sensing System: Current Progress and Ongoing Challenges
Abstract Staphylococcus aureusis a ubiquitous bacterium that has become a major threat to human health due to its extensive toxin production and tremendous capacity for antibiotic resistance (e. g., MRSA “superbug” infections). Amid a worsening antibiotic resistance crisis, new strategies to combat this deadly microbe that remove the selective pressure of traditional approaches are in high demand.S. aureusutilizes an accessory gene regulator (agr) quorum sensing network to monitor its local cellular population and trigger a devastating communal attack, like an invading horde, once a threshold cell density has been reached. The role of theagrsystem in a range of disease types is still being unraveled. Herein, we discuss the present‐day biochemical understanding ofagralong with unresolved details, describe its connection to the progression of infection, and review how chemical strategies have been implemented to study and intercept this signaling pathway. This research is illuminating the potential ofagras an anti‐virulence target inS. aureusand should inform the study of similar, yet less studied,agrsystems in related bacterial pathogens.
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- Award ID(s):
- 2108511
- PAR ID:
- 10418964
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Israel Journal of Chemistry
- Volume:
- 63
- Issue:
- 5-6
- ISSN:
- 0021-2148
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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