Hepatitis C: A Canadian perspective

Hepatitis C virus (HCV) infection is a global health problem associated with considerable morbidity and mortality. Estimates are that 250,000 Canadians were infected with HCV in 2013 and that 5,570 new cases were detected (1–3). Among those infected, nearly 75% develop chronic infection (4,5) and are at considerable risk of cirrhosis (6) and hepatocellular carcinoma (HCC) (7). Globally, complications of HCV results in approximately 0.5 million deaths per year (8, 9). HCV causes more years of life lost than any infectious disease in Canada (10), and it is the most common indication for liver transplantation (11). HCV-related health care costs, estimated at $160 million per year, are projected to increase to $260 million per year by 2032 as those currently infected develop progressive liver disease and its complications (2). There is no vaccine for HCV, and new infections remain a problem among several at-risk populations, including people who inject drugs (PWID), people who have been incarcerated, and HIV-positive men who have sex with men, with overlap between these groups (12, 13–15). Indigenous Canadians (Canadian First Nations, Inuit, and Métis populations) and First Peoples in countries around the world have a higher prevalence of HCV because they are overrepresented in some of the known risk groups.

The recent development of highly effective, well-tolerated, direct-acting antiviral agents (DAAs) for HCV is likely to produce a major turnaround in disease burden. With a cure rate of more than 95%, treatment is becoming increasingly feasible and has the potential to reduce HCV disease burden for infected persons and at the population level. Furthermore, the tolerability of the DAAs has made it possible to treat and cure complex, difficult-to-treat populations with advanced liver disease and even HCC. Achievement of sustained virologic response has implications beyond viral clearance; it is associated with improved long-term clinical outcomes, including all-cause mortality, and it also leads to economic benefits and improved quality of life (16). Although scaling up HCV treatment is essential to reverse ongoing trends in end-stage liver disease, data on the potential to reverse liver disease and HCC risk remain somewhat controversial (17). The success of DAAs in real life and the appropriate cascade of care for the different communities affected by HCV remain unknown. Finally, DAA cure does not prevent reinfection in high-risk populations such as PWIDs (18). In the absence of an effective prophylactic vaccine, new infections and reinfections remain a health risk and challenge.

The World Health Organization (WHO) has set elimination targets for 2030 to achieve an 80% reduction in HCV infections, 65% reduction in HCV-related mortality, and treatment of 80% of persons with HCV infection. Canada has signed onto this global strategy, but significant action is needed to reach these ambitious goals. Notably, Canada has yet to establish an action plan to achieve such elimination targets by 2030.

The Canadian Network on Hepatitis C (CanHepC) was established in 2015 through joint funding from the Public Health Agency of Canada and the Canadian Institutes of Health Research to establish a research continuum spanning HCV prevention, treatment, and outcomes and tackle the various challenges in reducing the burden of HCV. This network groups more than 100 investigators, trainees, and knowledge users from across Canada to establish a pipeline from discovery to implementation and to improve the lives of Canadians living with HCV.

CanHepC has partnered with the Canadian Liver Journal to publish a special topic series of articles on the problem of hepatitis C in Canada. The goal of this series is to provide an up-to-date evaluation of the hepatitis C landscape in Canada relative to the world and the key remaining research questions and challenges. First, we aim to provide a background framework for the establishment of a hepatitis C action plan to reach the WHO 2030 elimination targets. These articles are written by Canada’s experts on HCV and include updated estimates and projections of the epidemiology of HCV infection in Canada, including modelling the burden of the disease over the next decade.

Second, we have commissioned a series of articles that address HCV in special populations, including Indigenous populations, immigrants, PWID, and pediatric populations. Third, we provide a review of the problems associated with treatment delivery and the cascade of care, including the need to engage primary care providers and other health care practitioners in HCV treatment. To enhance prevention efforts, we need to monitor emerging trends and test novel prevention strategies for populations at greater risk of HCV primary and reinfections. Many infected individuals remain unaware of their status, and research is needed to improve HCV testing, particularly among subpopulations who are disengaged from the health care system, such as Indigenous and immigrant populations, and those with higher prevalence, such as baby boomers. Optimal testing strategies and population-based testing are discussed. Fourth, the remaining clinical challenges and the role of DAA treatment in reversing liver damage and immune dysfunction are addressed from both a clinical and a molecular–cellular perspective. Fifth, the role of the community in achieving HCV elimination is discussed. Finally, a research framework for a national action plan based on the WHO framework is proposed.

We believe that Canada is in a good position to achieve HCV elimination targets by 2030, and we hope that this series of articles will inform and bring together all stakeholders to work as a team within the proposed knowledge-to-action framework.

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