Detections of antimicrobial resistance phenotypes and extended-spectrum beta-lactamase (ESBL)- producing Salmonella spps and Escherichia coli O157:H7 in raw vegetables and fruits from open markets in Jimma town, Ethiopia and evaluation of hygiene and handling practices of vendors.

Abstract

Objectives: Despite of the health benefits of consumption of fresh vegetables and fruits, this product could be associated with food-borne bacterial pathogens, including infections with antibiotic-resistant strains especially in developing countries due to limited in knowledge, and hygienic practices. This study was conducted to provide evidence data on the rates of Salmonella spp. and E. coli O157:H7 contamination, the antimicrobial resistance profile, and extended-spectrum β-lactamase (ESBL)-producing strains in fresh vegetables and fruits sold in open-air markets at Jimma town, southwest Ethiopia. In addition, this study provided data on the hygiene and handling practices of vendors, which can help as impute to improve food safety and safeguard public health. A total of 242 salad samples were collected from three different kebeles and examined for the presence of Salmonella spp. and E. coli O157:H7 in the microbiology laboratory of Jimma University by using conventional microbiological techniques.

Results: Out of 242 samples tested, 12.8% (31/242) were contaminated with Salmonella spp. and E. coli O157. Of these, Salmonella spp. was detected in 10.7% (26/242) of the tested samples, whereas Escherichia coli O157:H7 was found in 2.1% (5/242) of samples. Fifty-three-point-8% of Salmonella spp. were resistant to ampicillin, 42.3% to co-trimoxazole, 46.2% to tetracycline, and 26.9% resistance was observed against each of ceftriaxone and cefotaxime. 40% of E. coli O157:H7 isolates were resistant against ampicillin, amoxicillin-clavulanic acid, and co-trimoxazole. Only one isolate was resistant to ceftriaxone and cefotaxime, and no resistance was observed against ceftazidime, gentamicin, ciprofloxacin, chloramphenicol, and meropenem. Four Salmonella spp. and one E. coli O157:H7 isolate with a total of 5/31 (16.1%) isolates were confirmed as the ESBL producers. Multidrug resistance (MDR) was detected in 23.1% of Salmonella and 20.0% of E. coli O157:H7. Hygienic and handling practices of vendors were poor, which could contribute to contamination of vegetables and fruits in the area.

Conclusions: Contamination of fresh salad vegetables with pathogenic bacteria could be a food safety concern in the study area. Hence, this finding suggests the need for attention by the concerned bodies to prevent the emergence and transmission of food-borne pathogens and antimicrobial-resistant strains through these food items in the study area.