CMAJ
Volume 187, Issue 16, 2015, Pages E473-E481

Domestic impact of tuberculosis screening among new immigrants to Ontario, Canada (Article) (Open Access)

Khan K.* , Hirji M.M. , Miniota J. , Hu W. , Wang J. , Gardam M. , Rawal S. , Ellis E. , Chan A. , Creatore M.I. , Rea E.
  • a Department of Medicine, Division of Infectious Diseases, University of Toronto, Canada, Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
  • b Public Health and Preventive Medicine Residency Program, Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada
  • c Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
  • d Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
  • e Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
  • f Department of Medicine, Division of Infectious Diseases, University of Toronto, Canada, Infection Prevention and Control, University Health Network, Canada
  • g Faculty of Medicine, University of Toronto, Toronto, ON, Canada
  • h Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
  • i Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
  • j Centre for Research on Inner City Health, Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
  • k Toronto Public Health, Dalla Lana School of Public Health, University of Toronto, Toronto, ON, Canada

Abstract

Background: All Canadian immigrants undergo screening for tuberculosis (TB) before immigration, and selected immigrants must undergo postimmigration surveillance for the disease. We sought to quantify the domestic health impact of screening for TB in all new immigrants and to identify mechanisms to enhance effectiveness and efficiency of this screening. Methods: We linked preimmigration medical examination records from 944 375 immigrants who settled in Ontario between 2002 and 2011 to active TB reporting data in Ontario between 2002 and 2011. Using a retrospective cohort study design, we measured birth country-specific rates of active TB detected through preimmigration screening and postimmigration surveillance. We then quantified the proportion of active TB cases among residents of Ontario born abroad that were detected through postimmigration surveillance. Using Cox regression, we identified independent predictors of active TB postimmigration. Results: Immigrants from 6 countries accounted for 87.3% of active TB cases detected through preimmigration screening, and 10 countries accounted for 80.4% of cases detected through postimmigration surveillance. Immigrants from countries with a TB (all-sites) incidence rate of less than 30 cases per 100 000 persons resulted in pre- and postimmigration detection of 2.4 and 0.9 cases per 100 000 immigrants, respectively. Postimmigration surveillance detected 2.6% of active TB cases in Ontario residents born abroad, and TB was detected a median of 18 days earlier in those undergoing surveillance than in those who were not referred to surveillance or who did not comply. Predictors of active TB postimmigration included radiographic markers of old TB, birth country, immigration category, location of application for residency, immune status and age. Interpretation: Universal screening for TB in new immigrants has a modest impact on the domestic burden of active TB and is highly inefficient. Focusing preimmigration screening in countries with high incidence rates and revising criteria for postimmigration surveillance could increase the effectiveness and efficiency of screening. © 2015 8872147 Canada Inc. or its licensors.

Author Keywords

[No Keywords available]

Index Keywords

immigrant proportional hazards model Proportional Hazards Models mass screening radiography health survey human immigration risk assessment middle aged birthplace statistics and numerical data Aged geographic distribution screening test Public Health Surveillance procedures disease surveillance Young Adult Humans migrant lung tuberculosis Adolescent Infant, Newborn Canada male preschool child Aged, 80 and over tuberculosis very elderly Emigrants and Immigrants Infant Child, Preschool newborn evaluation study female Incidence Article Retrospective Studies Ontario program evaluation adult immune response thorax radiography cohort analysis retrospective study Child
Link
https://www.scopus.com/inward/record.uri?eid=2-s2.0-84946017152&doi=10.1503%2fcmaj.150011&partnerID=40&md5=a6c4de9e2ca3f03aac04a438d732f913
DOI: 10.1503/cmaj.150011
ISSN: 08203946
Cited by: 17
Original Language: English