Dispersal of M. tuberculosis via the Canadian fur trade

Very little is known about the migration dynamics of Mycobacterium tuberculosis, the causative agent of tuberculosis. In order to better understand dispersal patterns of this important human pathogen, we studied European lineages of M.tuberculosis currently circulating in indigenous North American communities. Our analyses of genetic and other data suggest that the Canadian fur trade (1710-1870) was an important conduit of M.tuberculosis from European immigrants to Aboriginal peoples. M.tuberculosis populations appear to have persisted in indigenous communities at very low densities (bacterial Ne ~ 2) for about a century before abruptly expanding, following environmental changes that favored the pathogen. These unusual migration dynamics may help explain the low DNA sequence diversity observed among isolates of M.tuberculosis and likely contribute to difficulties in the global elimination of tuberculosis.

Contact

  Ash Pathak
  akp13@psu.edu
  814-867-2941