Identification of genetic relatedness of Mycobacterium ulcerans DNA from human and aquatic environmental samples: One Health approach to Buruli ulcer epidemiology

Abstract

Buruli ulcer (BU) disease is a neglected tropical disease caused by Mycobacterium ulcerans (M. ulcerans) pathogen, an environmental mycobacterium, which has affinity to inhabit aquatic niches. This disease causes debilitation mostly in children between 3 to 15 years, preventing them from having smooth schooling. Currently, the integration of One Health approach in tackling health challenges is gaining momentum because of the obvious identification of linkages that would proffer more cost-effective and sustainable solution. In this study, the agent-host-environment molecular inter-relatedness in the transmission of Buruli ulcer disease in selected communities in Ogun State, Nigeria contiguous to Benin Republic; a BU epicentre was explored. Extraction of Mycobacterium ulcerans DNA from suspected BU patients, water samples from rivers routinely accessed by the patients and aquatic fauna (fish and crabs) from the same rivers was done. Variable Number of Tandem Repeats (VNTR) was amplified from the extracted DNA using primers targeting loci 6 and 19; genetic markers used in the study of M. ulcerans diversity. The findings revealed that locus 19 of the VNTR showed presence of M.ulcerans population in water, fish and human samples at the band size of 344bp. Locus 6 further confirmed the initial finding indicating the presence of M. ulcerans population at the band size of 510bp in fish, crab, water and human samples. There is an indication of plausible involvement of fish and crab (animal component), water (environmental component) and humans (host component) in the transmission of M. ulcerans pathogen. From the findings in this work, a possible transmission pathway of M. ulcerans to humans was proposed.