Tracking tuberculosis in the past: the use of genealogical evidence

A series of mutations of tuberculosis, present in the 1990s among elderly persons in the Province of Quebec (Canada), is interpreted as the outcome of a suite of three episodes of high mobility. The most recent is the rapid urbanization of the 1950s. In the 1840s exceptional mobility was a feature of frontier settlement and exploitation of timber. Unusual mobility in the 1750s and 1760s was associated with wartime conditions of the British conquest of Quebec and re-settlement of Acadian refugees. The scenario was developed from cartographic analysis (using geographic information systems), genealogies of the human hosts, and molecular genetics of the bacterium.