Prevalence and antibiotic resistance of Enterococci in pork from supermarkets, retail markets, and slaughterhouses in Hanoi

Abstract

The use of antibiotics in livestock, combined with unsanitary slaughter conditions, not only increases the risk of food poisoning but also facilitates the transmission of antibiotic-resistant bacteria from food to humans. This study aimed to assess the contamination status and antibiotic resistance rates of Enterococci bacteria in pork samples collected from supermarkets, retail markets, and slaughterhouses in Hanoi between August 2019 and June 2020. Enterococci strains were isolated from pork samples, identified, and the antibiotic resistance genes were determined using PCR, while antibiotic resistance was assessed by the Kirby-Bauer method. Results showed that all 96 pork samples (100%) purchased from retail markets, supermarkets, and slaughterhouses were contaminated with Enterococci. Of the 588 strains isolated from the 96 pork samples, 259 strains (44%) were identified as E. faecalis and 97 strains (16.5%) as E. faecium. E. faecalis exhibited a higher rate of multidrug resistance compared to E. faecium (p<0.05). The proportion of E. faecalis resistant to five or more antibiotics was 42.9%, while for E. faecium, it was 26.8%. Additionally, 23.6% of E. faecalis were resistant to six antibiotics, and 2.7% were resistant to seven antibiotics tested in this study. These results indicate a potential risk of multidrug-resistant Enterococci being transmitted from contaminated food to humans during food consumption.