Genetic diversity and antimicrobial resistance ofCampylobacter jejuniisolates from Gambian children under five with moderate-to-severe diarrhoea and healthy Controls

Abstract

ABSTRACTIntroductionCampylobacteris a leading cause of bacterial gastroenteritis globally, but its molecular epidemiology remains poorly understood in sub-Saharan Africa. This study investigates the genotypic population structure ofCampylobacter jejuniisolates from children with moderate-to-severe diarrhoea (MSD) and healthy controls in The Gambia. Additionally, we determined the antimicrobial susceptibility levels of the isolates.MethodsAs part of the Global Enteric Multicenter Study (GEMS) in The Gambia, a total of 49C. jejuniisolates were collected from the stools of children under 5 years old, including 22 with MSD and 27 healthy controls. These isolates were subjected to multilocus sequence typing (MLST) and antimicrobial susceptibility testing using the disc-diffusion method.ResultsTheC. jejuniisolates belonged to 22 sequence types (STs), ten of which were novel. The most common STs were ST-353 (19.1%, 9/47), ST-7784 (12.7%, 6/47), and ST-1038 (10.6%, 5/47). All isolates were fully susceptible to erythromycin, tetracycline, gentamicin and chloramphenicol, with two isolates (4.4%, 2/45) resistant to ciprofloxacin and nalidixic acid. Antimicrobial resistance or intermediate susceptibility to trimethoprim-sulfamethoxazole, cefotaxime and ampicillin was observed in 91.1% (41/45), 90.9% (40/44), and 44.4% (20/45) of the isolates, respectively. There was no strong evidence linkingC. jejuniantimicrobial susceptibility or MLST genotype to MSD status.ConclusionThis study provides the first overview of the high genotypic diversity of humanC. jejuniisolates in The Gambia and reveals low-level resistance among the isolates to antibiotics commonly used to treat campylobacteriosis. The study contributes to understanding the epidemiology and resistance patterns ofC. jejuniin this region.