Frequency, antibiotic resistance, and serogroups of Salmonella among chicken meat specimens in Tehran, Iran

Background and Objective: Salmonella is one of the leading causes of foodborne illnesses worldwide which has become an important issue today due to the increasing drug resistance. This study was aimed to detect the frequency and diversity of Salmonella serogroups and drug resistance patterns among poultry meat samples distributed in Tehran, Iran.   Materials and Methods: In this cross-sectional study, 100 samples of poultry meat were prepared from authorized distributors of meat products from 22 districts of Tehran. All samples were analyzed by standard method and characterization of the isolates were done using biochemical, polymerase chain reaction, and serogrouping methods. Antibiogram was done using disk diffusion method.   Results: The results showed that Salmonella was present in 75% (75/100) of the chicken meat samples. Chicken meat isolates were predominantly belonged to serogroup C (88%, 66/75), while other isolates belonged to serogroup B (2.6%, 2/75), serogroup D (5.3%, 4/75), and non-group A–D Salmonella isolates (5.3%, 4.75). While resistance to tetracycline (59%) was the most common resistance phenotype in these isolates, concurrent resistance to 3 classes of antibiotics (3DR) was the most common type of multidrug resistance (MDR) phenotype among them.   Conclusion: In this study, high rate of contamination with Salmonella was observed in the chicken meat samples. Dominance of antibiotic resistance in these isolates showed their possible risk for transmission of resistance gene markers to the human gut microbiota through food chain.