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Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus (MRSA)

Published on: February 9, 2011

Isolation of meticillin-resistant Staphylococcus aureus (MRSA) from swine in Japan

Kotaro Baba1, Kanako Ishihara, Manao Ozawa

  • 1National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1 Tokura, Kokubunji, Tokyo 185-8511, Japan.

International Journal of Antimicrobial Agents
|August 10, 2010
PubMed

Insights

Meticillin-resistant Staphylococcus aureus (MRSA) was found in less than 1% of Japanese swine nasal samples. The study did not detect the swine-associated MRSA ST398 strain in this population.

Area of Science:

  • Veterinary Microbiology
  • Antimicrobial Resistance
  • Food Safety

Background:

  • Meticillin-resistant Staphylococcus aureus (MRSA) sequence type (ST) 398 is a significant pathogen in livestock globally.
  • Understanding MRSA prevalence in swine is crucial for public health and food safety.

Purpose of the Study:

  • To investigate the prevalence of MRSA, with a specific focus on ST398, in Japanese swine populations.
  • To characterize any isolated MRSA strains regarding their genetic type and antimicrobial resistance profile.

Main Methods:

  • Collection of 115 nasal swabs and 115 fecal samples from swine across 23 farms in eastern Japan.
  • Isolation and identification of MRSA using standard microbiological techniques.
  • Multilocus sequence typing (MLST) and spa typing for strain characterization.
  • Antimicrobial susceptibility testing of isolated MRSA strains.

Main Results:

  • MRSA was detected in only one nasal swab (0.9% prevalence); no MRSA was found in fecal samples.
  • The isolated MRSA strain was identified as ST221 (by MLST) and t002 (by spa typing), not the swine-associated ST398.
  • The MRSA isolate displayed resistance to ampicillin, meticillin, and dihydrostreptomycin, but remained susceptible to a broad range of other clinically relevant antibiotics.

Conclusions:

  • The overall prevalence of MRSA in Japanese swine appears to be low.
  • The specific swine-associated MRSA ST398 strain was not detected in this study population.
  • The findings highlight the importance of ongoing surveillance for MRSA in livestock.

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