Original Research

Food animals as reservoirs and potential sources of multidrug-resistant diarrheagenic E. coli pathotypes: Focus on intensive pig farming in South Africa

Shima E. Abdalla, Akebe L.K. Abia, Daniel G. Amoako, Keith Perrett, Linda A. Bester, Sabiha Y. Essack
Onderstepoort Journal of Veterinary Research | Vol 89, No 1 | a1963 | DOI: https://doi.org/10.4102/ojvr.v89i1.1963 | © 2022 Shima E. Abdalla, Akebe L.K. Abia, Daniel G. Amoako, Keith Perrett, Linda A. Bester, Sabiha Y. Essack | This work is licensed under CC Attribution 4.0
Submitted: 13 July 2021 | Published: 20 January 2022

About the author(s)

Shima E. Abdalla, Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
Akebe L.K. Abia, Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
Daniel G. Amoako, Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
Keith Perrett, Epidemiology Section, KwaZulu-Natal Agriculture and Rural Development-Veterinary Service, Pietermaritzburg, South Africa
Linda A. Bester, Biomedical Resource Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa
Sabiha Y. Essack, Antimicrobial Research Unit, College of Health Sciences, University of KwaZulu-Natal, Durban, South Africa


Share this article

Bookmark and Share

Abstract

Background: Diarrheagenic E. coli (DEC) strains are a major cause of diarrheal diseases in both developed and developing countries. Healthy asymptomatic animals may be reservoirs of zoonotic DEC, which may enter the food chain via the weak points in hygiene practices.

Aim: We investigated the prevalence of DEC along the pig production continuum from farm-to-fork.

Methods: A total of 417 samples were collected from specific points along the pig production system, that is, farm, transport, abattoir and food. E. coli was isolated and enumerated using Colilert. Ten isolates from each Quanti-tray were selected randomly and phenotypically identified using eosin methylene blue agar selective media. Real-time polymerase chain reaction (PCR) was used to confirm the species and to classify them into the various diarrheagenic pathotypes. Antimicrobial susceptibility was determined against a panel of 20 antibiotics using the Kirby-Bauer disk diffusion method and EUCAST guideline.

Results: The final sample size consisted of 1044 isolates, of which 45.40% (474/1044) were DEC and 73% (762/1044) were multidrug-resistant. Enteroinvasive E. coli (EIEC) was the most predominant DEC at all the sampling sites.

Conclusion: The presence of DEC in food animal production environments and food of animal origin could serve as reservoirs for transmitting these bacteria to humans, especially in occupationally exposed workers and via food. Adherence to good hygienic practices along the pig production continuum is essential for mitigating the risk of transmission and infection, and ensuring food safety.


Keywords

diarrheagenic E. coli; multidrug resistance; intensive pig farming; farm-to-fork; low-income countries; South Africa; multiple-antibiotic resistance index; biosecurity

Metrics

Total abstract views: 1752
Total article views: 948


Crossref Citations

No related citations found.