Zhao, Jiahao2025-05-082025-05-082025-05-082025-05-07https://hdl.handle.net/10012/21709Background: Hepatitis D virus (HDV) is an important health concern in Canada. HDV is a viral infection can cause a rapid progression to inflammatory response in the liver, resulting in liver cirrhosis, hepatocellular carcinoma (HCC) and liver-related death. HDV is a derivative viral infection of hepatitis B virus (HBV). HDV infections can be acute or chronic. Chronic infections can lead to long term illness, liver cirrhosis or liver death. HDV infections can happen simultaneously, HBV and HDV infections happen at the same time, known as coinfection. HDV infections can also occur chronologically, patients already infected with Chronic hepatitis B (CHB) will then be infected with HDV, known as superinfection. Currently, no known cure for HDV infection, only available treatment is pegylated interferon alfa. Various new therapies are being developed due to limited effectiveness of pegylated interferon alfa. Bulevirtide (BLV) is a treatment that has shown promising efficacy. Objective: The objectives of this thesis are to: (1) estimate the overall prevalence of HDV among immigrants in Canada. (2) assess the cost-effectiveness of HDV screening and treating patients with bulevirtide, pegylated interferon alfa-2a and combined therapy compared to no screening for HDV. Methodology: A literature review was conducted to gather all relevant data on HDV. The prevalence estimation for HDV among immigrants in Canada was calculated based on a weighted average analysis by estimating the HBV population in Canada and then estimating HDV population using the HBV population estimation. A state transition model representing the natural progression of CHB and HDV was developed in TreeAge Pro to assess the cost-effectiveness of three screening and treating strategies. Analyses were performed from a public payer perspective with a lifetime time horizon and a 1.5% annual discount rate. One way sensitivity analysis and probabilistic analysis have been conducted to assess uncertainty. Results: Estimated HDV prevalence among HBV infected immigrants in Canada in 2021 was to be 7.7%. This is equivalent to an overall HDV prevalence rate of 0.24%, around 20,102 immigrants. HDV screening and treating with pegylated interferon alfa-2a monotherapy is cost-effective. Our analysis resulted in mean cost of $288,062 and a 22.96 QALY for screening and treating with pegylated interferon alfa-2a monotherapy versus $283,716 and 22.76 QALY for no HDV screening and treatment. With an ICER of $21,808/QALY. However, HDV screening and treating with BLV monotherapy and HDV screening and treating with combined therapy (BLV plus pegylated interferon alfa-2a) were both not cost-effective compared to no HDV screening and treatment. Our analysis resulted in ICER values of $329,015/QALY and $199,841/QALY for screening and treating with BLV and screening and treating with combined therapy, respectively. From a clinical perspective, all screen and treat HDV strategies showed a reduction in cases of liver related outcomes in decompensated cirrhosis, hepatocellular carcinoma and liver death. Conclusion: The estimated prevalence of HDV showed that a reasonable number of immigrants living in Canada with HDV remain undiagnosed. The results of cost-effectiveness study showed that screening for HDV and treating can increase clinical benefits. The results of the thesis can provide policy makers with actionable recommendation in re-assessing the current HDV screening recommendation in Canada among our immigrant population.enchronic hepatitis bhepatitis d viruscost-effectiveness analysisMaster Thesis