5.2. The Feasibility of HBV Elimination by 2030
HBV elimination, per the epidemiological definition, means a reduction to zero of HBV incidence in defined geographical areas due to deliberate efforts. Presently, HBV elimination aligns with the 2016 WHO targets for viral HBV infections, focusing on controlling viral hepatitis by reducing its incidence, morbidity, and mortality to locally acceptable levels rather than absolute elimination [
16,
249]. The global initiative for HBV elimination by 2030, outlined by WHO, encompasses three primary objectives: establishing a world free from viral transmission of HBV, ensuring individuals with viral hepatitis access safe, affordable, and effective care, and eliminating viral hepatitis as a major public health threat by 2030 (with a note that complete elimination may not be achieved). Additionally, the aim is to substantially decrease the incidence of chronic viral hepatitis and the associated morbidity and mortality [
11,
16].
The feasibility of global HBV elimination is rooted in the virus’s characteristics, reliable diagnostic assays, and cost-effective measures. These measures involve implementing universal HBV immunization, antiviral treatment for highly viremic mothers in the third trimester to prevent MTCT, HBV screening in blood donors, adopting safe injection practices, implementing stringent infection-control programs to reduce HBV infections, and providing antiviral treatments for patients with HBV infection [
240]. Despite the ambitious task of achieving global HBV elimination by 2030, substantial work is imperative in the coming few years.
The available evidence suggests that the ambitious goal of achieving global HBV elimination by 2030 faces significant challenges. Despite the existence of tools to reach these goals since 2015, they remain insufficient or absent in various countries and regions, including high-income nations. Globally, HBV diagnosis rates are alarmingly low, averaging only 8% [
250,
251]. While certain areas make strides in prophylaxis and prevalence targets for HBV infection, studies emphasize that all regions must significantly increase rates of diagnosis and access to treatment to meet the global targets [
12,
19,
251].
Unfortunately, given the staggering number of individuals chronically infected with viral hepatitis (257 million) and its devastating global burden (almost 900,000 annual deaths) [
175] and coupled with the current efforts to combat the disease, achieving these targets in the next remaining years appears unlikely, particularly in resource-limited settings. WHO has advocated for multiple key interventions to achieve these targets, yet implementation remains lacking in most locations [
175]. For instance, attaining a 90% HBV immunization coverage, including HBV birth-dose vaccine coverage, proves challenging in regions like Africa, with current HBV birth-dose vaccine coverage estimated at 11% or even lower in resource-constrained areas [
245]. Similarly, increasing antiviral treatment provision to 80% by 2030 seems extremely challenging, especially in low- and middle-income countries (LMICs), where less than 5% of individuals infected with HBV or HCV are currently tested and enrolled in care and treatment programs [
175]. In many LMICs, affordable access to viral hepatitis testing and treatment is nearly impossible, posing a significant barrier to scaling up screen-and-treat interventions [
242]. High-income countries face their challenges, with millions remaining undiagnosed and infected individuals often belonging to vulnerable populations (undocumented migrants, injection drug users, homeless individuals) who are challenging to reach and enroll in care. In various locations, including LMICs, where the population is aging and untested, there is a potential for an increase in mortality due to viral hepatitis in 2030 compared to 2015. Lastly, tracking progress on WHO elimination targets necessitates not only the development of national hepatitis plans by countries but also establishing surveillance systems to measure the incidence and burden of liver disease, currently either nonexistent or of poor quality in most LMICs [
175].
While recognizing commendable initiatives by the WHO in collaboration with different stakeholders to initiate the elimination of viral hepatitis, an urgent need arises for developing and implementing realistic strategies tailored to diverse environments and specific populations. This imperative involves a heightened mobilization of civil society, health policymakers, and funders, as the current commitment to the fight against viral hepatitis remains notably inadequate. In comparison to other infectious diseases such as HIV and malaria, viral hepatitis faces substantial underfunding for both research and elimination efforts.
The WHO implores all countries and regions to invest in eliminating hepatitis by incorporating costing, budgeting, and financing elimination services within their universal health coverage plans. Achieving this objective necessitates not only effective treatment but also comprehensive policies addressing the prevention of new infections, financial structures, political will, stakeholder engagement, and integration within the healthcare system. The fusion of prevention and treatment to combat viral hepatitis is a feasible approach, albeit requiring substantial investments in healthcare system strengthening and the complete continuum of viral hepatitis services. This investment is expected to yield direct, indirect, and cross-sectoral economic benefits by saving lives and alleviating the cost burden of the disease on individuals, their families, and the state [
246].
The estimated cost of implementing key interventions in low- and middle-income countries (LMICs) between 2016 and 2021 amounts to US
$11.9 billion, with the principal cost drivers being testing and treatment for hepatitis B and C [
24]. Economic analyses in various regions highlight the cost-effectiveness of population-based approaches to testing and treating, emphasizing the need for a strategic investment of
$6 billion annually to avert 4.5 million premature deaths by 2030 and more than 26 million deaths beyond that target date. However, if medicines remain inaccessible and patent-protected in 13 LMICs, the cost would escalate to
$118 billion [
247].
For instance, to align with the WHO’s goal of eliminating viral hepatitis, global diagnosis coverage should surge from 9–20% in 2015 to 90% in 2030. Additionally, treatment coverage must advance from 7–8% in 2015 to 80% in 2030 [
241]. In clinical practice, treatment coverage hinges on diagnosis followed by linkage to care, requiring countries to intensify national plan efforts. Nevertheless, critical gaps persist in current policies.
In a 2017 survey encompassing all 194 Member States, approximately 70% (135 countries/regions) formulated national plans for WHO elimination goals. However, fewer than 50% secured funding, and even in funded cases, the allocated amounts fell short of covering the entire plan [
237]. High-income countries confront ‘diagnostic burnout,’ treating easily accessible patients while leaving marginalized populations, such as homeless individuals, prisoners, people who inject drugs, and a significant portion of the general population, undiagnosed. Consequently, only 11 high-income countries are currently on track to eliminate viral hepatitis by 2030 [
248].
This lack of progress signifies a policy failure. In 2019, as part of the Lancet Gastroenterology & Hepatology Commission, major policy deficiencies were highlighted in 66 studied countries [
242]. These deficiencies encompassed a lack of available national epidemiological data and publicly funded screening programs for viral hepatitis. Across countries, there was a diverse spectrum of policy responses, with some having all recommended policies in place. In contrast, others ranked poorly, often with only a single policy, such as mandatory screening of blood products [
249]. Moreover, many countries lacked estimates of the potential economic impact of viral hepatitis on their populations [
249].
5.4. Key areas of progress towards the 2030 elimination goals:
Significant strides have been made since 2015 towards achieving the World Health Organization’s (WHO) ambitious 2030 elimination goals for hepatitis. The WHO has been instrumental in providing crucial tools for the development of national strategies, test-and-treat guidelines for hepatitis B and C, cost-effectiveness quantitative analysis (WHO CHOICE), a global hepatitis reporting system, and consolidated strategic information guidelines [
259,
260,
261].
A 2019 study revealed that 62% of Member States had formulated national hepatitis plans, with 27% in the draft stage by 2017. Of these plans, 58% included domestic funding [
237]. Forty-five countries/regions have contributed data to the new global reporting system for hepatitis.
Regarding HBV infection, there has been notable progress in immunization coverage. By the end of 2018, the HBV infant vaccine had been introduced in 189 countries/regions, achieving global coverage of three vaccine doses estimated at 84% [
245].
Historically, the WHO WPR had the world’s highest prevalence of chronic HBV infection. Various countries in this region, including Papua New Guinea, the Philippines, Vietnam, Lao People’s Democratic Republic, and China, had prevalence rates exceeding 5%. In 2017, the WPR successfully reduced the prevalence of chronic HBV infection to 0.93% in 5-year-old children, meeting the WHO target [
257]. GAVI’s expanded support for HBV vaccine birth-dose coverage has been crucial, potentially averting 0.3–1.2 million perinatal infection-related deaths and 1.2–1.5 million cases from 2021–2025.
Despite this progress, estimates indicate insufficient HBV birth-dose vaccine coverage globally, particularly in Africa, where only 11% of newborns receive the recommended dose within 24 hours [
245]. Civil society bodies like the World Hepatitis Alliance continue to play a pivotal role in engaging donors and stakeholders, ensuring an evidence-based approach to the response.
Examining Taiwan as a case study reveals substantial advancements toward the 2030 elimination goals. These include preventing vertical HBV transmission through immunization and antiviral treatment for highly viremic mothers, ensuring widespread access to potent, safe, and affordable HBV treatments, and initiating changes in reimbursement policies for HBV therapy. Taiwan’s proactive approach, including universal HBV vaccination since 1986, significantly reduces HBsAg carriage rates and expands treatment indications. The country aims to reach the WHO goals by 2025, five years ahead of the 2030 deadline [
202].
Developed over a decade ago, the latest generation of nucleoside analogues for HBV has demonstrated enduring safety and effectiveness in preventing CHB-related liver complications, such as cirrhosis and HCC [
258]. The introduction of generic medications has not only decreased treatment costs but has also expanded treatment accessibility in numerous countries. Additionally, a crucial stride towards enhancing global vaccine coverage involves the creation of polyvalent vaccine formulations encompassing the HBV vaccine for infants and children.
Advancements in HBV therapeutics have been witnessed recently, with industry investments paving the way for new drugs targeting various steps in the HBV life cycle and immune responses. Although no new therapeutics have reached phase III trials, the development of combination therapies holds promise for a functional cure, suppressing HBV replication after a finite course of treatment [
259].
The emergence of viral hepatitis patient associations, non-governmental groups, and national hepatitis programs in many countries/regions signifies growing public and political awareness, contributing to the global effort to eliminate hepatitis [
20]
5.5. Strategies for Achieving HBV Elimination by 2030
The development of an effective HBV vaccine has substantially contributed to controlling the spread and progression of HBV-related diseases. However, projections indicate that the persistence of HBsAg prevalence requires intervention. Post-2050, numerous countries are expected to make strides toward established goals. Specifically, only three countries are projected to achieve a 90% reduction in HBV incidence, with none reaching a 65% reduction in mortality compared to 2015, and no country is expected to meet all current HBV elimination targets [
260].
While notable progress has been made, meeting the WHO’s ambitious goals for HBV elimination by 2030 necessitates continual monitoring and addressing persisting barriers hindering effective prevention, diagnosis, and treatment interventions. Critical examination of these barriers aims to identify practical solutions, paving the way for a more holistic and equitable approach towards WHO targets.
Each country and community must develop practical and sustainable strategies tailored to their unique circumstances. The primary focus for the next seven years should be on prevention through universal birth-dose vaccination for all newborns globally. Additionally, health education, tailored to different high-risk populations, is crucial in increasing awareness of HBV infection risk factors, consequences of chronic liver disease, and the benefits of screening and effective treatment regimens.
Another critical aspect involves increasing public awareness of HBV infections through mass screening programs and linking patients to point-of-care facilities [
261]. The imperative task of addressing undiagnosed individuals, known as the “missing millions,” involves combating the barriers of awareness, limited healthcare access, and diagnostic challenges on a global scale. Initiatives like the World Hepatitis Alliance’s “Find the Missing Millions” campaign are pivotal in heightening awareness and improving diagnostic endeavors worldwide [
261,
262].
To ensure the success of elimination strategies, we must make concerted efforts to eradicate the stigma associated with HBV. Due to public misconceptions regarding HBV transmission, individuals with CHB infection often face unjust bias attributed to perceived ‘bad behaviors,’ leading to discrimination based on the fear of casual transmission [
267].
The adoption of Micro-elimination strategies targets individual population segments for quicker and more efficient treatment and prevention interventions [
264]. These programs may address districts with high prevalence, identify pockets of high prevalence within districts, take measures to prevent transmission, address risk factors, and identify target groups to treat infection and prevent transmission. For example, these programs may focus on antenatal screening, infant vaccination, catch-up vaccination, vaccination of persons who inject drugs, prisoners, decompensated cirrhosis, veterans, or patients with hemophilia, and homosexuals. Creating a lifetime Markov model demonstrates that strategies to vaccinate, prevent, or treat CHB in high-risk populations significantly reduce cirrhosis, decompensation, liver cancer, and chronic hepatitis death compared to no intervention [
106]. Micro-elimination strategies are tailored with realistic and well-defined targets and goals. These are pragmatic, with a shorter time to achievement, and costs can be predicted. Micro-elimination projects may generate a template in a small, geographically defined population that may then be used to model services for larger intervention programs. Successful micro-elimination efforts encourage further public health strategies. Micro-elimination of HBV appears cost-effective and positively impacts long-term outcomes with screening and treatment or vaccination strategy compared with no intervention [
264].
In the context of HBV, imperative initiatives involve implementing programs for the timely administration of HBV vaccines at birth in Africa and other highly endemic regions [
245]. Given that a significant number of HBV-infected individuals reside in resource-poor areas, urgent actions are required to enhance access to diagnosis, treatment, and cure. Considering that HBV is a primary contributor to HCC, it is essential to establish screening programs for HCC in individuals infected with HBV [
265].
The path to HBV elimination demands sustained commitment, improved coordination among diverse HBV prevention programs, and heightened efforts to diagnose and treat eligible individuals. Given the substantial occurrence of MTCT, comprehensive testing for HBV in pregnant women is crucial. If infection is detected, administering HBIG to newborns promptly is vital to prevent transmission. Addressing challenges in HBIG administration in Low- and Middle-Income Countries (LMICs), where MTCT is prevalent, underscores the need for HBV diagnosis and treatment strategies in eligible women of child-bearing age to mitigate MTCT. In general, broad-scale diagnosis and treatment of HBV-infected individuals are imperative for achieving HBV elimination [
12,
19,
254].
A pivotal objective for the upcoming decade is the discovery of agents that functionally cure HBV, moving beyond mere suppression.
Countries with limited resources require international investments in viral hepatitis programs encompassing prevention and treatment strategies. Additionally, enhancing blood safety and harm reduction programs, particularly among people who inject drugs, is vital to curtail HBV transmission. Reducing drug costs, including introducing generic agents, can elevate treatment coverage for HBV infections. Crucially, the development of curative regimens for HBV will significantly expedite the achievement of elimination goals [
266].
Regular monitoring and evaluation are indispensable for assessing the efficacy of implemented solutions and making necessary adjustments. By addressing these challenges comprehensively, we can expedite progress toward the 2030 goal of eliminating HBV ultimately saving millions of lives.