Buruli ulcer, tuberculosis and leprosy: Exploring the One Health dimensions of three most prevalent mycobacterial diseases: A narrative review

Οbjectives Although Buruli ulcer, tuberculosis, and leprosy are the three most common mycobacterial diseases, One Health dimensions of these infections remain poorly understood. This narrative review aims at exploring the scientific literature with respect to the presence of animal reservoir(s) and other environmental sources for the pathogens of these infections, their role in transmission to humans and the research on/practical implementation of One Health relevant control efforts. Methods The literature review was conducted using the online databases PubMed, Scopus, ProQuest and Google Scholar, reviewing articles that were written in English in the last 15 years. Grey literature, published by intergovernmental agencies, was also reviewed. Results For the pathogen of Buruli ulcer, evidence suggests possums as a possible animal reservoir and thus having an active role in disease transmission to humans. Cattle and some wildlife species are deemed as established animal reservoirs for tuberculosis pathogens, with a non‐negligible proportion of infections in humans being of zoonotic origin. Armadillos constitute an established animal reservoir for leprosy pathogens with the transmission of the disease from armadillos to humans being deemed possible. Lentic environments, soil and other aquatic sources may represent further abiotic reservoirs for viable Buruli ulcer and leprosy pathogens infecting humans. Ongoing investigation and implementation of public health measures, targeting (sapro)zoonotic transmission can be found in all three diseases. Conclusion Buruli ulcer, tuberculosis and leprosy exhibit important yet still poorly understood One Health aspects. Despite the microbiological affinity of the respective causative mycobacteria, considerable differences in their animal reservoirs, potential environmental sources and modes of zoonotic transmission are being observed. Whether these differences reflect actual variations between these diseases or rather knowledge gaps remains unclear. For improved disease control, further investigation of zoonotic aspects of all three diseases and formulation of One Health relevant interventions is urgently needed.