Analysis of Biochemical Variability and Antimicrobial Resistance Profile of Escherichia coli Strains Isolated from the Vegetable Food Chain in Niamey, Niger

Escherichia coli (E. coli), is important both in terms of its frequency and the severity of the conditions it causes. It is a commensal of the human digestive tract. The presence of E. coli in food products indicates direct or indirect faecal contamination due to hygiene deficits during product preparation. The objective of this study was to analyze the biochemics variability and level of antibiotic resistance of Escherichia coli strains isolated from vegetables produced and sold in Niamey. A total of 124 vegetable samples and 29 irrigation water samples were collected and analyzed. The biochemical characteristics were searched on the API24 gallery. The antibiotic resistance phenotype was determined using the standard Kirby-Bauer agar diffusion method. Approximately, 05.64% of vegetable samples were contaminated with E. coli, with tomato samples most affected (08.57%), followed by onion samples (08.33%). The study of the biochemical characteristics divides the strains into three (3), of which Group 1 is characterized by the absence of DHA and Groups 2 and 3 by the presence of DHA. The most frequently observed resistance phenotypes concerned CRO, AMC, ATM, SXT and TET. The presence of multi-resistant strains of Escherichia coli in vegetables testifies the potential risk associated with the consumption of these vegetables. It is important to look for the potential resistance and virulence genes of these strains for better management of infectious diseases.