Genotyping antibiotic resistance properties of escherichia coli and campylobacter jejuni associated with diarrhoea in young children in the Vhembe District

Abstract

Background: Diarrhoea continues to threaten the lives of young children in Sub-Saharan Africa. While antibiotic resistance among enteric pathogens such as Escherichia coli (E. coli) and Campylobacter spp. is increasing, surveillance of antimicrobial resistance genes (ARG) is limited in Africa. The need for such studies in Africa was demonstrated by our published review of the literature on surveillance of molecular resistance mechanisms like blaCTX-M. Therefore, this study sought to investigate the genotypic (blaCTX-M and gyrA) antibiotic resistance profiles of bacteria causing diarrhoea in young children in the Vhembe district. Methods: A cross-sectional surveillance was done between August 2020 and August 2021. Diarrhoeal (lose, watery) and non-diarrhoeal (normal, solid) stool samples were collected from children under the age of five at selected hospitals and clinics around the Vhembe District. The Kirby Bauer Disk Diffusion technique was used to screen for antibiotic susceptibility, and PCR and sequencing were used for molecular characterization of antibiotic resistance genes. Results: Of the E. coli positive samples, 39% (18/46; 12 diarrhoeal and 6 non-diarrhoeal) had multi-drug resistance (MDR) to at least three antibiotics, with 33% (6/18) and 11% (2/18) having fluoroquinolone (gyrA) and ß-lactam (blaCTX-M) resistance mechanisms, respectively. Five percent (1/18) of the samples carried both gyrA and blaCTX-M genes. The prevalence of Campylobacter in diarrhoeal stools was 13.8% and gyrA gene was partially detected. Conclusion: Children under the age of two in the Vhembe District continue to be at risk from diarrhoea due to antibiotic resistant Escherichia coli and Campylobacter. This study raises awareness of the prevalence of MDR, and aids medical professionals in implementing the appropriate treatment. Future research should consider concurrent studies on clinical and environmental samples to determine the possible role of livestock and river water as carriers of antibiotic resistance genes.