Occurrence and Characteristics of Methicillin-Resistant and -Susceptible <i>Staphylococcus aureus</i> Isolated from the Beef Production Chain in Korea.
Lee. Haeng Ho HH; Lee. Gi Yong GY; Eom. Hong Sik HS; Yang. Soo-Jin SJ
Key Findings
- Only 5 MRSA and 11 MSSA isolates were found among 1,285 beef‑related samples, indicating low overall prevalence.
- All MRSA isolates (5/5) and some MSSA isolates (2/11) were multi‑drug resistant.
- MRSA strains were more resistant to the antimicrobial peptide LL‑37 than MSSA strains.
- No link was observed between tetracycline/zinc resistance and multi‑drug resistance in these isolates.
- The study recommends ongoing surveillance of livestock, meat, and people in contact with meat to prevent human transmission.
Practical Outcomes
- For biohackers and health‑optimizers, the main takeaway is heightened awareness that some beef‑associated bacteria can resist both antibiotics and natural immune peptides like LL‑37. While the risk appears low, it underscores the importance of proper meat handling, thorough cooking, and hygiene to minimize exposure to resistant microbes.
Summary
A Korean study looked at how often drug‑resistant Staph bacteria show up in the beef supply chain. They found only a few MRSA and MSSA cases, but the MRSA strains were often resistant to many antibiotics and also to the natural antimicrobial peptide LL‑37. This suggests that even low‑level contamination could carry tough bacteria.
Abstract
The emergence and persistence of methicillin-susceptible <i>Staphylococcus aureus</i> (MSSA) and methicillin-resistant <i>S. aureus</i> (MRSA) in livestock animals have been reported as a potential risk factor for transmission to humans. In this study, we investigated the nationwide prevalence and characteristics of MRSA and MSSA in the Korean beef production system, including retail markets, slaughterhouses, and cattle farms. From a total of 1,285 samples, only 5 MRSA strains were isolated: from a farmer (1 ST72 MRSA), a carcass sample from a slaughterhouse (1 ST72 MRSA), and beef cattle (3 ST5 MRSA). In addition, 11 MSSA strains were isolated from beef cattle (n=3), humans (1 farmer, 1 slaughterhouse worker, and 4 retail market workers), and carcass samples (n=1) and slaughterhouse environment (n=1). Although the prevalence of MRSA and MSSA in beef cattle was much lower than that reported in pigs, 5/5 MRSA and 2/11 MSSA strains displayed multiple drug resistance (MDR) phenotypes. Unlike the swine-associated MRSA, no correlation was found between tetracycline/zinc resistance and MDR phenotype. However, MRSA strains had an identical set of staphylococcal enterotoxins and exhibited enhanced levels of resistance to antimicrobial peptides (PMAP-36 and LL-37) compared to the MSSA strains. In conclusion, continued and systemic surveillance of livestock, meat products, and humans in close contact with livestock/meat products is necessary to prevent the transmission of MRSA and MSSA to humans.
Study Information
pubmed
2020
2020-04-30T00:00:00.000Z
10.5851/kosfa.2020.e20