Abstract:
The Lineage 2–Beijing (L2–Beijing) sub-lineage of Mycobacterium tuberculosis has
received much attention due to its high virulence, fast disease progression, and
association with antibiotic resistance. Despite several reports of the recent emergence of
L2–Beijing in Africa, no study has investigated the evolutionary history of this sub-lineage
on the continent. In this study, we used whole genome sequences of 781 L2 clinical
strains from 14 geographical regions globally distributed to investigate the origins
and onward spread of this lineage in Africa. Our results reveal multiple introductions
of L2–Beijing into Africa linked to independent bacterial populations from East- and
Southeast Asia. Bayesian analyses further indicate that these introductions occurred
during the past 300 years, with most of these events pre-dating the antibiotic era. Hence,
the success of L2–Beijing in Africa is most likely due to its hypervirulence and high
transmissibility rather than drug resistance.
