Prevalence and Antibiotic Resistance of Campylobacter Species in Chicken Meat and Stool Samples in Shiraz

Background and Objectives: Campylobacter is the most common foodborne bacterial cause of human enteric diseases in several industrialized countries. This pathogen is frequently found in the intestinal tract of a wide variety of food-producing animals, especially in poultry. The consumption of poultry is identified as a major cause of Campylobacter infection in humans. The aim of this study was to determine the prevalence of Campylobacter species in chicken meat and stool samples of patients with acute diarrhea, and to compare antibiotic resistance profiles of the isolates. Materials and methods: A total of 100 chicken meat samples came from different municipal districts of Shiraz, and 290 stool samples were collected from patients with acute diarrhea, referred to Nemazee and Dastgheyb hospitals, between September 2018 and August 2019. Campylobacter spp. isolation was done through standard microbiological methods. Specific primers were used for the identification of the Campylobacter isolates at species level by PCR. Minimum inhibitory concentration (MIC) of six antibiotics (tetracycline, nalidixic acid, ciprofloxacin, ampicillin, gentamicin and erythromycin) was determined for Campylobacter isolates, using the agar dilution method of CLSI 2016. Results: Seventeen (17%) and 22 (7.6%) Campylobacter strains were isolated from samples of chicken meat and of stool, respectively. While majority of the isolates (86%) from human sources belonged to C. jejuni, only 35 % of the isolates from chicken meat were associated with this species. In chicken meat samples, the most prevalent species was C. coli (65%). The resistance levels of isolates from stool samples to nalidixic acid, erythromycin, ampicillin were 87%, 90% and 31%, respectively. While all isolates from chicken meat were resistant to nalidixic acid, resistance to both erythromycin and ampicillin was observed in 88% of the isolates. Most effective antibiotic in-vitro was gentamicin irrespective of the source of isolates.Conclusion: Here we report an alarming level of multidrug resistance in Campylobacter isolates both from chicken meat and human stool. The results of this study support the idea that chicken meat could be a major source of Campylobacter infections in humans. In order to confirm this finding, molecular typing of the isolates from both sources is suggested.