Figure 1. Number of foreign-born people with MDR-TB diagnosed in Alberta by year of arrival. The number of cases is represented by the solid line and the trend in MDR-TB case counts by the dashed line.Footnote 7
The graph shows the number of foreign-born people diagnosed with MDR-TB (solid line) in Alberta and the trend in MDR-TB case counts (dashed line) relative to year of arrival in Canada. The horizontal axis shows year of arrival, grouped in two-year increments (pre-1981, 1981-82, 1983-84, 1985-86, 1987-88, 1989-90, 1991-92, 1993-94, 1995-96, 1997-98, 1999-00, 2001-02, 2003-04, 2005-06, 2007-08, 2009-10). The vertical axis on the left side of the graph shows the number of cases.
Between 1981-82 and 2001-02 there were four periods (of two years) that reported no cases, four periods that reported one case, and three periods that reported two cases. Between 2003-04 and 2009-10 there were no periods that reported no cases, one that reported one case, one that reported three cases, one that reported four cases, and one that reported seven cases. Two of the 27 MDR-TB cases reported in the paper in the calendar years 1982-2011 arrived before 1981.
The graph shows a slow but steady upward trend in MDR-TB case counts, from approximately one case among persons arriving to Canada in the early to mid-1980s, to roughly three cases among persons arriving in 2009-2010.
Figure 2. Time from arrival in Canada to diagnosis of foreign-born, culture-positive tuberculosis cases by drug susceptibility pattern of incident case isolate (1997-2008)Footnote 8
The graph shows the time from arrival in Canada to time of diagnosis of culture-positive TB disease among foreign-born cases by resistance pattern for the years 1997 to 2008. The horizontal axis shows time from arrival in Canada to time of diagnosis (in years), ranging from 0 to 55. The vertical axis on the left side of the graph shows the number of reported cases, with susceptible cases represented by green bars, MDR cases by blue bars, and drug-resistant non-MDR cases by red bars. The line graph shows the cumulative proportion of foreign-born TB cases diagnosed since their time of arrival in Canada, with one line for MDR cases (dark blue/purple), one line for drug-resistant non-MDR cases (light blue) and one line for drug-susceptible cases (orange).
MDR cases presented earlier after arrival than resistant non-MDR cases and resistant non-MDR cases presented earlier after arrival than drug-susceptible TB cases.