Figure 2. Estimated proportion of recent versus remote tuberculosis infection among derivation cohort contacts.

A comparison between close contacts of active pulmonary TB patients within each MTB lineage group. Light coloured bars: proportion estimated to have remote TB infection based on the calculated probability of latent TB at the time of immigration to Canada (see methods for details). Dark coloured bars: remaining TST positive (out of total) assumed to have recent TB infection (i.e. equivalent to TST conversion). Abbreviations: TB = tuberculosis.