Purpose: In the present study, we aimed to investigate the contamination level and antibiotic resistance pattern of S. aureus among industrial, antibiotic-free organic/pasture grown and farmers markets poultry products from the Maryland-Washington DC metro area.
Methods: A total of 96 poultry whole carcass samples including 32 samples from 7 farmers markets, 28 samples from 3 organic retail supermarkets and 36 samples from 3 conventional retail supermarkets from the Maryland-Washington DC metro area were collected over a period of eight months starting from February to September of 2014.
Results: A total of 24 S. aureus isolates were recovered from 96 whole poultry carcass samples and the prevalence of S. aureus were 25.0%, 14.29%, and 33.3% in retail poultry meats collected from farmers markets, organic and conventional retail supermarkets, respectively. Both single and multidrug-resistant isolates were detected in 58.3% (7/12) isolates from conventional retail meat products but none from farmers markets or organic retail meat isolates. Conventional retail meat isolates were found to be resistant to both erythromycin (50.0%) and tetracycline (58.3%). We also detected an MRSA isolate harboring mecA gene in conventional retail meat which showed co-resistance towards erythromycin, tetracycline, and vancomycin.
Significance: Although this was a small study in a limited geographical area, this study serves as an indication that Staphylococci including MRSA are present in retail chicken meat. Additional studies are needed in order to assess the risk of MRSA colonization in poultry gut and the workers who handle raw meat.