Population Genomics and Molecular Epidemiology of Mycobacterium ulcerans

Bacterial population genomics is providing detailed insights into Mycobacterium ulcerans evolution, showing how and when this pathogen emerged and spread across the world and in particular within Africa and Australia, the regions most affected by Buruli ulcer (BU). This chapter summarizes our current understanding of the emergence of M. ulcerans from a Mycobacterium marinum ancestor, and describes how at least two evolutionary bottlenecks, that included acquiring the specific capability to make mycolactones, led to a specific lineage of M. ulcerans causing the majority of human disease. At local scales, detailed longitudinal, comparative genomic studies of M. ulcerans isolates recovered from BU endemic regions have revealed patterns of pathogen spread that are providing useful new understandings around BU transmission.