Prevalence, genotyping and antibiotic resistance of Listeria monocytogenes and Escherichia coli in fresh beef and chicken meats marketed in Zanjan, Iran

Background and Objectives: The aim of present study was to evaluate the prevalence of Listeria monocytogenes and Escherichia coli, characterization and antimicrobial resistance of their serotypes and genotyping profiles in fresh beef and poultry meats marketed in Zanjan, Iran. Materials and Methods: A total of 90 (45 chicken and 45 beef) samples were collected from January to June 2018 focusing on retail meat stores of Zanjan city, Iran. Foodborne pathogen detection and antimicrobial resistance of isolates performed by PCR and disc diffusion methods, respectively. Simplex PCR method was used for screening hly and uidA genes in L. monocytogenes and E. coli isolates, respectively. Results: Findings revealed high contamination in beef and chicken meats with E. coli (68.89% and 88.89%, respectively) and L. monocytogenes (53.33% and 46.67%, respectively). The most likelihood of E. coli isolates belonged to E. coli 13479 serotype. All L. monocytogenes isolates from beef and chicken meat samples had high similarity with serotypes L. monocytogenes strain NCTC 10357 and strain MF 4545, respectively. Multi drug resistance (MDR) was seen in both L. monocytogenes and E. coli isolates. Conclusion: This study shows an insight of the current status of beef and chicken meat contamination maketed in Zanjan, Iran with E. coli and L. monocytogenes isolates (high contamination rate), their genotypic profile, epidemiological relationship and antimicrobial resistance (AMR) that should be considered as a significant public health concern in Zanjan, Iran.