Extensively drug-resistant and heat-resistant Enterococcus faecalis and Enterococcus faecium in ready-to-eat meat products

The presence of extensively drug-resistant and heat-resistant Enterococcus faecalis and Enterococcus faecium in ready-to-eat meat products poses a significant public health risk due to their ability to survive thermal processing, persist in the food chain, and disseminate antimicrobial resistance, thereby increasing the risk of foodborne transmission and limiting treatment options. This study evaluated the prevalence, heat-resistance, virulence, and antimicrobial resistance profile of Enterococcus isolated from ready-to-eat (RTE) meat products in Mansoura, Egypt. All (100%, 135/135) examined RTE samples (45 each of shawarma sandwiches, Hawawshi, and pastrami slices) were contaminated with Enterococcus. PCR targeting the sodA gene verified that 63.3% (171/270) of Enterococcus isolates were E. faecium and 36.7% (99/270) were E. faecalis. The gelE and ace virulent genes were detected in 71.1% and 65.2% of Enterococcus isolates, respectively. Absolute resistance (100%) of enterococcal isolates was found towards penicillin and imipenem, while 86.7%, 85.6%, and 41.9% were resistant to rifampin, vancomycin, and amoxicillin, respectively. All isolates were resistant to at least 4 antibiotics, and 96.3% were resistant to at least 6 antibiotics, with an average MAR index of 0.604. Interestingly, Enterococcus in RTE meat samples passed thermal microwave deactivation for 5 minutes, indicating a potent heat stability of this microorganism. The threat caused by virulent, heat-tolerant, vancomycin-resistant enterococci contaminating meat products highlights the risk associated with these pathogens. This emphasizes the urgent need for preventive measures and global strategies to control these emerging foodborne threats.