Demographics can help identify migrants to Canada at high risk of TB

Demographic characteristics can help identify groups of immigrants in Canada at high risk of tuberculosis (TB), according to new research in CMAJ (Canadian Medical Association Journal).

"Screening latent TB infection based on demographic factors at the time of immigration is a necessary first step toward eliminating TB in migrants to Canada," says Dr. James Johnston of the University of British Columbia and the BC Centre for Disease Control in Vancouver, BC.

The study examined TB outcomes in permanent residents of Canada who lived in BC between 1985 and 2012. Researchers sought to identify groups at highest risk of TB based on demographic characteristics when immigrating to Canada. TB rates increased with older age at the time of immigration, with people aged 65 years and older having the highest rates. People who emigrated from regions with highest TB incidence had TB rates in Canada more than 21 times that of people coming from regions with the lowest TB incidence.

"Our study adds to the understanding of long-term TB incidence in migrant populations in Canada by showing that rates remain elevated up to two decades after migration," write the authors.

The authors suggest that latent TB screening and treatment may be practical and high impact, and will help reduce TB incidence in some high-risk groups.