Detection and antibiogram profile of diarrheagenic Escherichia coli isolated from two abattoir settings in northwest Ethiopia: a one health perspective

Abstract

Background

Diarrheagenic Escherichia coli (E. coli) is a zoonotic pathogen that contaminates abattoir workers, slaughter environments, slaughter equipment, and carcasses during abattoir processing. Infection with E. coli is associated with the consumption of contaminated food and water, and it is a potential threat to the health and welfare of both humans and animals. Hence, this study aimed to detect diarrheagenic E. coli and assess its antibiogram profile in two abattoir settings, in one health lens.

Methods

A cross-sectional study in one health approach was conducted from December 2020 to June 2021. A total of 384 samples from abattoir workers’ hands, carcasses, knives, cattle feces, abattoir water and effluents were collected. Bacterial culture and biochemical tests were conducted to isolate E. coli, while conventional polymerase chain reaction was performed to identify virulence genes. The antibiogram of diarrheagenic E. coli was tested against nine antimicrobials using the Kirby Bauer disk diffusion method.

Results

A total of 115 (29.95%) E. coli were isolated from the 384 samples, and from these isolates, about 17 (14.8%) were confirmed to be diarrheagenic E. coli (DEC). Among the DEC pathotypes, nine (52.94%), five (29.4%), and three (17.65%) were Shiga toxin-producing, enterohemorrhagic, and enterotoxigenic E. coli, respectively. While 14 (82.35%) DEC isolates harbored the stx2 gene, five (29.41%) the eae gene, five (29.41%) the hlyA gene and three (17.65%) harbored the st gene. All the DEC isolates were resistant to erythromycin and vancomycin; whereas, they were susceptible to ampicillin, nalidixic acid and norfloxacin. Furthermore, 64.7% of DEC isolates showed resistance to both ceftazidime and kanamycin and 88.24% of the isolates showed multidrug resistance.

Conclusion

This study detected DEC isolates having different virulence genes, which showed single and multiple antimicrobial resistance. Given the existing poor hygienic and sanitary practices along the abattoir-to-table food chain, coupled with the habit of raw meat consumption, this result indicates a potential public and animal health risk from the pathogen and antimicrobial resistance.