HomeCanada is a leading destination for migrants, both in numbers received and on a per-population basis, receiving on average more than 250,000 immigrants and refugees each year. As a result, there are now approximately 7.5 million foreign-born persons living in Canada, accounting for 21.9% of the population.1 Over the past 50 years, there has been a major demographic shift in the source countries of new migrants to Canada. Before the 1970s, most individuals immigrating to Canada originated from Western European countries. Since that time, the proportion of immigrants originating from intermediate or high TB-incidence countries such as in Asia, Africa and Latin America has increased. In the 2016 census, an estimated 68% of migrants to Canada originated from countries with an intermediate or high TB incidence.1
The two main administrative classifications of migrants arriving in Canada are 1) permanent residents who come to Canada to resettle; and 2) temporary residents who are visiting, studying or working in Canada on a time-limited basis. Permanent and temporary residents are further classified into several subgroups based on their immigration status (see Table 1). In addition, Canada receives millions of international visitors each year; in 2019, 32 million nonresident travelers arrived in Canada.2 Most immigrant groups apply for permission to come to Canada while still living in their countries of origin, although asylum seeker claimants who apply upon or after arrival in Canada are an important exception. As well, there are a substantial number of undocumented migrants living in Canada, estimated to be anywhere from 20,000 to 500,000 persons.3
Table 1. Classification of international migration to Canada (arrivals in 2019).
| Immigration category | Number of persons a |
|---|---|
| Permanent residentsb | |
| Economic class | 197,000 |
| Family reunification | 91,000 |
| Humanitarian and compassionate | 5,000 |
| Refugees and protected persons | 49,000 |
| Total | 342,000 |
| Temporary residentsb | |
| International students | 402,000 |
| Foreign workers (Temporary Foreign Worker Program and International Mobility Program) | 405,000 |
| Total | 807,000 |
| Nonresidents – visitors or travelers | 32,000,000 |
Tuberculosis in Canada has increasingly become concentrated in specific population groups such as the foreign-born, Indigenous populations, and people with medical, social and/or behavioral risk factors, such as human immunodeficiency virus (HIV) infection, homelessness and injection drug use.5 In 2019, foreign-born persons accounted for 74.2% of all active TB diagnoses in Canada, and had an overall 40-fold higher incidence of TB than the non-Indigenous, Canadian-born population (15.8 vs 0.4 cases/100,000 population), although rates are much higher in certain subgroups of immigrants.6 Among foreign-born TB patients with a known immigration status at the time of diagnosis, approximately three-quarters of diagnoses occurred among citizens and permanent residents, and 15% occurred among temporary residents (i.e., students, foreign workers and visitors).6 Most TB in the foreign-born population in Canada occurs as a result of reactivation of TB infection that was acquired in their country of origin. TB infection prevalence increases depending on the country of origin, with interferon-gamma release assay (IGRA) positivity ranging from 2.9% (95% CI 0.2-31.7) for foreign-born persons from countries with TB incidence <30 cases per 100,000 people to 36% (95% CI 26.3-41.7) for those from countries with ≥200 cases per 100,000 people (range 19.9-41.6% for tuberculin skin test (TST) positivity).7,8
Switch To: Français