Monitoring and Evaluation of Antibiotic Resistance Pattern of Escherichia coli Isolated from Drinking Water Sources in Ardabil Province of Iran

Antibiotic resistance is rapidly spreading among bacteria, such as Escherichia coli, which have been discharged into water sources by humans and animals, in part due to genes carried by integrons. The goal of this study was to track and assess the pattern of antibiotic resistance among Escherichia coli strains isolated from drinking water sources in Iran’s Ardabil province.

Escherichia coli strains were isolated and identified using standard biochemical and microbiological techniques from Ardabil province’s water supply sources in 2019 and 2020. The class 1 integron gene was detected using the polymerase chain reaction (PCR). The disk diffusion method was used to determine antibiotic resistance and sensitivity.

The Int I gene was found in 47 out of 200 isolates (23.5%). The antibiotic streptomycin had the highest resistance (100%), whereas gentamycin, ciprofloxacin, tobramycin, tetracycline, cefipime, imipenem, meropenem, chloramphenicol, and trimethoprim-sulfamethoxamide had the lowest resistance. Gentamycin, ciprofloxacin, tobramycin, tetracycline, cefipime, imipenem, meropenem, and trimethoprim-sulfamethoxazole, on the other hand, had the highest sensitivity of 100%, while streptomycin had the lowest (0%). Also, the highest level of pollution of Escherichia coli in drinking water supply sources in the province is in Parsabad city (42.86%), and the lowest level of pollution is in Kosar city (6.67%).

According to the findings of this study, the high prevalence of Escherichia coli strains resistant to the antibiotic streptomycin circulating in water sources should be considered a major problem in terms of antibiotic resistance spreading among bacteria in water.