Isolation of methicillin-resistant Staphylococcus aureus from small ruminants and their meat at slaughter and retail level in Greece

Lett Appl Microbiol. 2015 Nov;61(5):498-503. doi: 10.1111/lam.12485. Epub 2015 Oct 1.

Abstract

Methicillin-resistant Staphylococcus aureus (MRSA) presents major health risk for humans causing serious nosocomial and community-acquired infections. Asymptomatic food-producing animal carriers and their meat may represent potential reservoirs for human infections. The aim of this study was to investigate the prevalence of MRSA in small ruminants raised under free-range conditions and their meat at slaughter and retail level in Northern Greece. Staphylococcus aureus was isolated from 9·6% of the examined samples. All isolates were resistant at least to one antibiotic, whereas 59·3% of them were multidrug resistant (MDR) exhibiting resistance to three or more antibiotic classes. The higher resistance rates were observed against penicillin (100%), tetracycline (74%), clindamycin (59·3%) and erythromycin (51·9%). Resistance to cefoxitin was exhibited by 22·2% of the isolates, but only one isolate was found to carry the mecA gene and belonged to spa type t127. This is the first time this type of Staph. aureus is isolated in Greece from the surface of a small ruminant's carcass. The presence of multidrug resistant Staph. aureus, and especially MRSA, in small ruminants and their meat, represents a potential threat for the spread of this pathogen in the community.

Significance and impact of the study: This study is the first report on methicillin-resistant Staphylococcus aureus in small ruminants and their meat at slaughter level in Greece, elucidating a possible vehicle food for transmission to humans. These results suggest that human or animal sources could be involved in meat contamination and thus sources of contamination require investigation to control the dispersion of MRSA in the community.

Keywords: antimicrobial susceptibility; methicillin-resistant Staphylococcus aureus; pulsed-field gel electrophoresis; small ruminant meat; spa typing.

MeSH terms

  • Abattoirs
  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Cross Infection
  • Drug Resistance, Multiple, Bacterial
  • Food Contamination / analysis
  • Greece / epidemiology
  • Humans
  • Meat / microbiology*
  • Meat-Packing Industry
  • Methicillin-Resistant Staphylococcus aureus / drug effects
  • Methicillin-Resistant Staphylococcus aureus / genetics
  • Methicillin-Resistant Staphylococcus aureus / isolation & purification*
  • Microbial Sensitivity Tests
  • Prevalence
  • Ruminants / microbiology*
  • Staphylococcal Infections / epidemiology*
  • Staphylococcal Infections / microbiology
  • Staphylococcal Infections / transmission

Substances

  • Anti-Bacterial Agents