Antimicrobial sensitivity profile of Escherichia coli isolated from water along the production line at Sands Fish Farm, Kanyanya, Kampala, Uganda

Abstract

Antimicrobial resistance in pathogenic bacteria is a serious “one health” issue. Production water in fish farms located around urban informal settlements is prone to heavy fecal contamination. This is because most of these farms are mostly fed by surface streams flowing in areas with poor sanitation and hygiene facilities. This exposes the water to potentially pathogenic multi-drug-resistant strains of E. coli. Similarly, the spread of AMR and associated infections through aquatic foods represents a major concern for public health. This study aimed at (1) identifying the antimicrobial agents used at Sands fish farm and in the neighboring community; (2) measuring the antimicrobial sensitivity profile of Escherichia coli in aquaculture production water samples from Sands fish farm, Kanyanya. Samples of Aquaculture production water were collected from various locations in Sands fish farm. The antimicrobial resistance pattern was determined against commonly used antibiotics, using the Kirby-Bauer Disc diffusion method. Out of 18 samples collected (100%), E. coli were isolated. For Tetracyclines (Oxytetracycline), Penicillin, Ampicillin, and Erythromycin, all the isolates had mean inhibition zones <11 mm, <14 mm, <13 mm, and <13 mm respectively. Since they fall within the set criteria for resistance, all the isolates showed 100% resistance to Oxytetracycline, Penicillin, Erythromycin, and Ampicillin at all sampling sites. There was 100% susceptibility of E. coli to Streptomycin at the hatchery tank, inlet channel, outlet channel, supply channel, and culture ponds. However, E. coli at the reservoir showed 100% resistance to Streptomycin with a 0.0 mm zone of inhibition. The high resistance in E. coli might be because the water source/stream mixes with sewage in the runoffs. The runoff contains fecal bacteria E. coli as well as the residues of the antimicrobial agents tested due to poor dispersal mechanisms of the drug leftovers and the packaging materials. In conclusion, the production waters at Sands fish farm contained high levels of multi-drug resistant E. coli. Therefore, it’s necessary to treat the water before use and educate people regarding the rational use of antibiotics and the safe disposal of antibiotic-containing waste.