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Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)
08:51

Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)

Published on: November 4, 2016

Molecular epidemiology and antimicrobial resistance mechanisms of methicillin-resistant Staphylococcus aureus

S Türkyilmaz1, S Tekbiyik, E Oryasin

  • 1Adnan Menderes Universitesi, Veteriner Fakültesi, Mikrobiyoloji AD, Aydin, Turkey.

Zoonoses and Public Health
|November 17, 2009
PubMed

Insights

This study identified multi-drug resistant methicillin-resistant Staphylococcus aureus (MRSA) in Turkish dairy milk. Findings highlight potential animal-to-human transmission and the need for strict hygiene and antibiotic stewardship to control MRSA spread.

Area of Science:

  • Veterinary Microbiology
  • Antimicrobial Resistance
  • Food Safety

Background:

  • Mastitis in dairy cows is a significant economic concern.
  • Methicillin-resistant Staphylococcus aureus (MRSA) is a growing public health threat.
  • Understanding MRSA epidemiology in livestock is crucial for One Health approaches.

Purpose of the Study:

  • To identify and characterize MRSA strains from bovine milk in Turkey.
  • To determine antimicrobial resistance profiles and genetic relatedness of isolated MRSA.
  • To investigate the potential for MRSA transmission between animals and humans.

Main Methods:

  • Isolation and identification of S. aureus from bovine milk samples.
  • Antimicrobial susceptibility testing and molecular typing (SCCmec, spa, MLST, PFGE).
  • Detection of specific resistance genes and Panton-Valentine leucocidin (PVL) toxin gene.

Main Results:

  • 16 out of 93 S. aureus isolates were identified as MRSA.
  • MRSA strains exhibited multi-drug resistance, with high resistance to erythromycin, clindamycin, chloramphenicol, and gentamicin.
  • Molecular typing revealed distinct pulsotypes, SCCmec types (IV and III), spa types (t190, t030), and MLST types (ST8, ST239).
  • Specific resistance genes (tet(M), aac(6)-aph(2), erm(A), erm(B)) were identified.
  • No PVL toxin gene was detected in the MRSA isolates.

Conclusions:

  • The study identified multi-drug resistant MRSA in Turkish dairy herds, suggesting potential circulation between animals and humans.
  • The genetic diversity of MRSA strains indicates possible clonal spread.
  • Implementing strict hygienic measures and rational antibiotic use is recommended to prevent resistance selection and dissemination.
  • Consideration of farm workers as potential MRSA carriers is important in control strategies.

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