RGHI member Dr. Mehlika Toy joined ESHPM from Stanford University School of Medicine earlier this year. Here she introduces her research on developing cost-effectiveness models to answer complex public health questions and guide evidence-based policy decisions. Her work has informed decision-making in countries such as Türkiye, China, the Netherlands, and the United States.
Global Public Health Burden
Viral hepatitis B infection continues to be a global health problem, with hepatitis delta virus, only infecting individuals with hepatitis B, further contributing to the burden. While significant progress has been made toward eliminating hepatitis B as a public health threat, hepatitis delta still requires greater attention. Cost-effectiveness analysis has emerged as a valuable tool in guiding policy makers to make decisions in the allocation of resources and determining which interventions can achieve impact in eliminating these diseases as public health problems.
Hepatitis B: A Preventable Health Threat
Hepatitis B is a vaccine-preventable liver disease and the leading cause of liver cancer globally. Many infected individuals experience mild symptoms or none at all, leading to undiagnosed cases. However, acute infections can cause fatigue, loss of appetite, dark urine, and jaundice, lasting for months or even resulting in death from liver failure. Those who do not clear the infection may develop chronic hepatitis B, which can lead to cirrhosis, liver failure, or liver cancer. Approximately 254 million people worldwide are living with chronic hepatitis B, contributing to over 60% of liver cancer cases. While not curative, suppressive therapy can prevent disease progression and reduce complications. Recent reductions in antiviral prices, thanks to effective generics, have improved access to treatment.
As a public health researcher specialising in cost-effectiveness analysis, I focus on enhancing health economic evaluations in low- and middle-income countries to guide resource allocation for better population health. Let me share examples of our work.
WHO Goals for Hepatitis Elimination
In 2016, in response to the UN’s 2030 Sustainable Development Goal to combat viral hepatitis, the World Health Organisation launched its first global health sector strategy to eliminate viral hepatitis as a public health issue by 2030. This strategy aims to reduce hepatitis B transmission by 90% and increase diagnosis and treatment rates to 90% and 80%, respectively. Endorsed by all WHO member states, the strategy also targets a reduction in hepatitis B virus transmission by 90% by 2030, increasing diagnosis from 9% and treatment from 8% (in 2015) to 90% and 80%, respectively, with an overall goal of reducing hepatitis B-related deaths by 65% globally by 2030.
But are these goals still achievable and how much will it cost to potentially eliminate hepatitis? Together with Dr. Samuel So from Stanford University’s Asian Liver Center and Dr. David Hutton from the University of Michigan, in collaboration with the WHO, we set out to develop the hepatitis B calculator on the experience of the Hep C calculator. This is an online, open-access, interactive tool to estimate the cost-effectiveness of antiviral treatment for HBV. The tool to this date covers 28 countries which are designated as priority countries for HBV elimination by the WHO, which together account for 70% of the global HBV burden. This online tool allows stakeholders in a country to analyse cost-effectiveness by using different input parameters and settings for their population. These can be drug costs, rate of liver transplantation, the prevalence of the country etc. The timeline can also be set according to national preferences.
The Role of Cost-Effectiveness Analysis
Economic analysis has played a vital role in shaping health policy and securing investments for viral hepatitis elimination. In partnership with the WHO, we calculated what it would cost to eliminate hepatitis B and C in 67 high prevalence countries if treatment were included as part of Universal Health Coverage, a package of essential services that everyone has access to testing and treatment without incurring financial hardship. We assumed all the countries have access to testing and optimal drug procurement cost (US$30 per year for tenofovir, US$20 per year for disease monitoring, and US$ 20 per year for annual HBV DNA test). We estimated that the cost of long-term hepatitis B monitoring, and treatment is US$25.6 billion.
About 96% of hepatitis B cases are in low- and middle-income countries, with the highest burden in Africa and the Western Pacific. For example, China has nearly 90 million people living with HBV. Our cost-effectiveness study comparing generic and brand antivirals in China was recognised by WHO and helped successfully negotiate lower drug prices for antivirals. Delays in scaling up treatment could have serious consequences. In our study, a one-year delay in reaching WHO’s 80% treatment target in China would lead to an additional 334,000 HBV-related deaths and US$55 billion in future healthcare costs. These analyses help inform policymakers and support evidence-based decision making.
Strengthening Health Technology Assessment in Low- and Middle-Income Countries
Building health technology assessment (HTA) capacity in low- and middle-income countries through education, better data systems, and integration into national health systems is essential. Engaging local stakeholders, developing local expertise, and improving data collection can help create sustainable HTA systems that support informed, equitable, and cost-effective healthcare resource allocation.
Focusing on the Burden of Delta Hepatitis
Hepatitis delta virus (HDV) is the most severe form of viral hepatitis, with high prevalence regions including Central and Western Africa, Central Asia, Mongolia, Pakistan, The Amazonian Basin in South America, Greenland, Pacific Islands such as Kiribati and Nauru, the Middle East, Eastern Europe and the Eastern Mediterranean. The best way to control HDV is through HBV prevention with vaccination. However, cost-effectiveness studies are needed to assess testing and treatment strategies, particularly in HBV-endemic areas.
Türkiye is one such endemic region for HDV. Together with my colleagues from Koç University School of Medicine, we conducted a meta-analysis to estimate the region specific HDV prevalence in Türkiye. Our study estimated that the prevalence among outpatient clinic HBV patients in Wester, Central, and Eastern Türkiye ranges from 2.1%-9.8%. One might assume that HDV is more readily diagnosed in a country like Türkiye, where the virus is endemic, however, there has been limited investigation into whether appropriate diagnostic protocols are consistently followed across different regions and types of healthcare institutes. In collaboration with many regional stakeholders, we are now conducting a study to assess adherence to recommended HDV testing practices in Türkiye. This research will help us understand gaps in HDV diagnosis and inform the development of cost-effectiveness models for universal HDV testing among HBV-infected individuals.
