Prevalence and Characterization of Methicillin-Resistant Staphylococcus aureus Isolates from Retail Meat and Humans in Georgia

Abstract

There is increasing interest in the presence of Staphylococcus aureus, specifically methicillin-resistant S. aureus (MRSA), on retail meat products. In this study, staphylococci were isolated from retail pork and retail beef in Georgia, and MRSA from the products was compared to human MRSA from the same geographic area using broth microdilution antimicrobial susceptibility testing, multilocus sequence typing (MLST), spa typing, SCCmec typing, and pulsed-field gel electrophoresis (PFGE). S. aureus was isolated from 45% (45/100) of pork products and 63% (63/100) of beef products; mecA was detected in S. aureus from both pork (3/100; 3%) and beef (4/100; 4%). Fifty percent (50/100) of human S. aureus also contained mecA. Multidrug resistance was detected among MRSA from all sources. All MRSA (n ‫؍‬ 57) was SCCmec type IV, and nine different spa types were present among the isolates (t002, t008, t012, t024, t179, t337, t548, t681, and t1062). Four sequence types (ST5, ST8, ST9, and ST30) were detected using MLST; the majority of MRSA isolates belonged to ST8, followed by ST5. One retail beef MRSA isolate belonged to ST8, while the remaining three were ST5. In retail pork MRSA, ST5, ST9, and ST30 were observed. The majority of human MRSA isolates belonged to ST8. Thirty-seven MRSA isolates, one of which was a retail beef MRSA isolate, were pvl ؉ . Using PFGE, MLST, and spa typing, three retail beef MRSA isolates were found to be identical in PFGE pattern, ST, and spa type to two human clonal MRSA isolates (USA100 and USA300). One additional retail beef MRSA isolate had a PFGE pattern similar to that of a human MRSA isolate, whereas none of the retail pork MRSA isolates had PFGE patterns similar to those of human MRSA isolates. These data suggest that the retail beef samples were contaminated by a human source, possibly during processing of the meat, and may present a source of MRSA for consumers and others who handle raw meat.

Methicillin-resistant <i>Staphylococcus aureus</i> isolates from Iranian restaurant food samples: Panton-Valentine Leukocidin, SCCmec phenotypes and antimicrobial resistance

“…Absence of the PVL gene in the cases of food poisoning has been reported previously [22]. [23] reported similar results for the high prevalence of SCCmec IV in retail meat samples. They reported that all of the MRSA strains of beef and pork samples were positive for SCCmec IV which was higher than our findings.…”

Isolation of Methicillin-Resistant Staphylococcus aureus Strains Producing Enterotoxins A, K and Q From Chicken Meat in Isfahan, Iran, 2014

“…The isolation of MRSA from different meat samples was reported previously from different countries (16)(17)(18)(19)(20)(21)(22)(23). Another study (10) reported MRSA strains from poultries in Iran; therefore, the isolation of MRSA strains from chicken meat was not surprising.…”

Molecular characterization and detection of enterotoxins, methicillin resistance genes and antimicrobial resistance of Staphylococcus aureus from fish and ground beef

“…Therefore, S. aureus can be found commonly in various foods including meat (de Boer et al 2009, Jackson et al 2013) and fish (Da Silva et al 2010, Saito et al 2011. It is clear that contamination of food with this pathogen is often related to improper handling and storage conditions, as well as inadequate hygienic conditions and post-production microbial contamination (Ray 2004).…”

“…aureus causes serious diseases by producing various virulence factors and presents difficult therapeutic problems due to rapid development of resistance to many antimicrobial agents. The results of many studies on genetic diversity of S. aureus from different regions have been documented (Soltan et al 2010, Jackson et al 2013, Alibayov et al 2014. In Turkey, limited data are available on genotypic characterization of S. aureus from fish and meat.…”