Theme: Epidemiology & Public Health Research Year: 2019
Background: The Canadian burden of chronic hepatitis C (HCV) is highly concentrated among people
who inject drugs (PWID), a population experiencing high rates of incarceration in provincial prisons.
In such settings, HCV care and post-release linkage to care are hindered by high turnover rates,
frequent re-incarceration, and lack of standardized care pathways. Recent incarceration also
increases HCV acquisition through elevated injecting risks. It remains unknown, however, if and how
enhanced prison-based linkage to care interventions could contribute to HCV micro-elimination. We
aimed to assess the population-level impact of such strategies on HCV transmission among PWID in
Montréal.
Methods: We developed a dynamic compartmental model of HCV transmission among PWID in
Montréal, stratified by sex, incarceration, and injecting status. The model was calibrated to
reproduce epidemic trends (2003-2014) using a Bayesian framework. We evaluated the 5-year
impact of enhancing linkage to care (90% tested and 75% of those tested treated post-release) with
or without reducing the elevated injecting risk post-release by 50%. We estimated the relative
reduction in incidence and the prevented fraction of new infections, as compared to a status quo
scenario that maintains 2018 rates of testing, treatment, and coverage of harm reduction services.
Results: After five years, linkage to care post-release combined with risk reduction could reduce HCV
incidence by 31% (95%CrI: 20-39%) and prevent 12% (95%CrI: 7-16%) of new chronic infections, as
compared the status quo. Without post-release risk reduction, the incidence decrease would have
been of 19% (95%CrI: 12-24%) and the prevented fraction of 7% (95%CrI: 4-9%). Both scenarios
would treat the equivalent of 2% of all PWID annually, suggesting a high per capita population-level
impact.
Conclusion: For PWID in provincial prisons, prioritizing linkage to care and integrating post-release
risk reduction strategies could change the course of the epidemic and contribute to HCV microelimination in Montréal.
Disclosure of Interest Statement: MMG, JC, and NK report investigator-sponsored research grant
from Gilead Sciences, outside the scope of this work.