Laboratory Diagnostic Methods and Antibiotic Resistance Patterns of Staphylococcus aureus and Escherichia coli Strains: An Evolving Human Health Challenge

Raw ground meat is known as a transmission vehicle for biological agents that may be
harmful to human health. The objective of the present study was to assess microbiological quality
of the ground meats. A total of 280 samples of local and imported chilled meats were randomly
collected from retail shops in Buraydah City, Saudi Arabia. The meat samples were microbiologically
analyzed using standard methods, peptide mass fingerprinting (PMF) technique, MicroScan
Walkaway System (MicroScan) and qPCR System. The imported meat was more bacterially contaminated
than local meat, with variable contamination degrees of Staphylococcus aureus (40.33%),
Escherichia coli (36.13%), Hafnia alvei (7.56%), Pseudomonas spp. (6.72%), Salmonella spp. (5.88%) and
Aeromonas spp. (3.36%). PMF verified all the isolated bacteria by 100%, compared to 75–95%
achieved by MicroScan. The gene encoding flagellin (fliC) was recognized in 67.44% of E. coli strains,
while the thermonuclease (nuc) and methicillin resistance (mecA) genes were detected in 100% S.
aureus and 39.6% of methicillin-resistant S. aureus (MRSA) strains, respectively. The S. aureus and E.
coli strains were highly resistant to multiple antibiotics (e.g., ampicillin, amoxicillin-clavulanic acid
and cephalothin). For identifying various foodborne pathogens, PMF has been recognized as a powerful
and precise analytical method. In light of the increasing use of PMF to detect multidrug-resistant
bacteria, this study emphasizes the need for improved ways of treating and preventing pathogens,
as well as setting up monitoring systems to guarantee hygiene and safety in meat production