Prevalence and antibiotic resistance of Escherichia coli O157:H7 in beef at a commercial slaughterhouse in Moro, Kwara State, Nigeria

Busayo I Ajuwon; Sola K Babatunde; Olatunji M Kolawole; Adeyinka E Ajiboye; Abosede H Lawal

doi:10.1099/acmi.0.000289

Prevalence and antibiotic resistance of Escherichia coli O157:H7 in beef at a commercial slaughterhouse in Moro, Kwara State, Nigeria

Access Microbiol. 2021 Nov 11;3(11):000289. doi: 10.1099/acmi.0.000289. eCollection 2021.

Authors

Busayo I Ajuwon^{1

2}, Sola K Babatunde³, Olatunji M Kolawole⁴, Adeyinka E Ajiboye², Abosede H Lawal⁵

Affiliations

¹ National Centre for Epidemiology and Population Health, Research School of Population Health, College of Health and Medicine, The Australian National University, Canberra, ACT 2601, Australia.
² Department of Biosciences and Biotechnology, Faculty of Pure and Applied Sciences, Kwara State University, Malete, Nigeria.
³ Department of Natural and Environmental Sciences, Faculty of Science, Crown-Hill University, Ilorin, Kwara State, Nigeria.
⁴ Department of Microbiology, Faculty of Life Sciences, University of Ilorin, Ilorin, Nigeria.
⁵ Centre for Occupational and Environmental Public Health, Cardiff School of Sport and Health Sciences, Cardiff Metropolitan University, Cardiff, UK.

Abstract

Background: Gastroenteritis due to foodborne disease is a leading cause of death in developing countries. In Nigeria, there is an increasing demand for beef. Yet, there is no surveillance for Escherichia coli O157:H7 contamination of raw beef and little is known about the carriage of this pathogen in Nigeria's livestock.

Methods: A total of 415 samples, including 180 cow carcass swabs, 180 caecal content samples, 16 water samples, 25 hand swabs and 14 knife swabs were collected at a large abattoir in the Moro region of Kwara State, Nigeria. The samples were enriched in modified tryptone broth containing novobiocine, and plated onto Sorbitol-MacConkey agar (Oxoid SR0172E) supplemented with 0.05 mg l^-1 cefixime and 2.5 mg l^-1 potassium tellurite (Oxoid) (CT-SMAC). Indole-producing isolates were confirmed serologically by serotyping with antisera specific for the O157 and H7 antigens. The E. coli O157:H7 isolates were further tested for their susceptibility to antibiotic agents using the disc diffusion method. Commercially available Gram-negative multi-discs (Oxoid) comprising nitrofurantoin (30 µg), ampicillin (5 µg), ceftazidime (30 µg), gentamicin (10 µg), ciprofloxacin (5 µg), augmentin (30 µg), ofloxacin (5 µg) and cefuroxime (30 µg) were tested.

Results: Overall, 16 (3.9 %) samples were contaminated with E. coli O157:H7, of which 10 (5.6 %) were isolated from carcass swabs, 4 (2.2 %) from caecal content samples and 2 (12.5 %) from water. All isolates were multidrug-resistant (MDR), with resistance to ampicillin, ceftazidime and cefuroxime being the most common.

Conclusion: This study provides evidence to suggest that E. coli O157:H7 exists in the beef production chain. The pathogen reveals a high frequency of multidrug resistance, suggesting that consumers and handlers of such meat are at risk of contracting antibiotic-resistant E. coli O157:H7-associated foodborne disease. Routine monitoring of antibiotic resistance is critical to uncovering novel therapeutic strategies that will help inform clinical practice guidelines.

Keywords: E. coli O157:H7; antibiotic susceptibility; beef; gastroenteritis; prevalence.