title: Stochastic agent-based modeling of tuberculosis in Canadian Indigenous communities.
abstract: In Canada, active tuberculosis (TB) disease rates remain disproportionately higher among the Indigenous population, especially among the Inuit in the north. We used mathematical modeling to evaluate how interventions might enhance existing TB control efforts in a region of Nunavut.
  
  
  
  We developed a stochastic, agent-based model of TB transmission that captured the unique household and community structure. Evaluated interventions included: (i) rapid treatment of active cases; (ii) rapid contact tracing; (iii) expanded screening programs for latent TB infection (LTBI); and (iv) reduced household density. The outcomes of interest were incident TB infections and total diagnosed active TB disease over a 10- year time period.
  
  
  
  Model-projected incidence in the absence of additional interventions was highly variable (range: 33-369 cases) over 10 years. Compared to the 'no additional intervention' scenario, reducing the time between onset of active TB disease and initiation of treatment reduced both the number of new TB infections (47% reduction, relative risk of TB = 0.53) and diagnoses of active TB disease (19% reduction, relative risk of TB = 0.81). Expanding general population screening was also projected to reduce the burden of TB, although these findings were sensitive to assumptions around the relative amount of transmission occurring outside of households. Other potential interventions examined in the model (school-based screening, rapid contact tracing, and reduced household density) were found to have limited effectiveness.
  
  
  
  In a region of northern Canada experiencing a significant TB burden, more rapid treatment initiation in active TB cases was the most impactful intervention evaluated. Mathematical modeling can provide guidance for allocation of limited resources in a way that minimizes disease transmission and protects population health.
authors.affiliation: Dalla Lana School of Public Health, University of Toronto, University of Toronto, Toronto, ON, Canada. atuite@hsph.harvard.edu.|Harvard T.H. Chan School of Public Health, 1633 Tremont Street, Boston, MA, 02120, United States. atuite@hsph.harvard.edu.
authors.forename: Ashleigh R
authors.initials: AR
authors.lastname: Tuite
authors.affiliation: Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON, Canada.
authors.forename: Victor
authors.initials: V
authors.lastname: Gallant
authors.affiliation: Nunavut Department of Health, Iqaluit, NU, Canada.
authors.forename: Elaine
authors.initials: E
authors.lastname: Randell
authors.affiliation: Centre for Communicable Diseases and Infection Control, Public Health Agency of Canada, Ottawa, ON, Canada.
authors.forename: Annie-Claude
authors.initials: AC
authors.lastname: Bourgeois
authors.affiliation: Department of Population Medicine, University of Guelph, Guelph, ON, Canada.
authors.forename: Amy L
authors.initials: AL
authors.lastname: Greer
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002170:Canada / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D055985:Latent Tuberculosis / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D020957:Nunavut / Q000453:epidemiology; D044382:Population Groups / Q000706:statistics & numerical data*; D012307:Risk Factors; D014376:Tuberculosis / Q000453:epidemiology*; D055815:Young Adult
keywords: Canada; Latent TB infection; Mathematical model; Nunavut; Public health; Simulation; TB; Tuberculosis