Global prevalence, treatment, and prevention of hepatitis B virus infection in 2016: a modelling study

BACKGROUND: The 69th World Health Assembly approved the Global Health Sector Strategy to eliminate viral hepatitis by 2030. Although no virological cure exists for hepatitis B virus (HBV) infection, existing therapies to control viral replication and prophylaxis to minimise mother-to-child transmission make elimination of HBV feasible. We aimed to estimate the national, regional, and global prevalence of HBsAg in the general population and in the population aged 5 years in 2016, as well as coverage of prophylaxis, diagnosis, and treatment. METHODS: In this modelling study, we used a Delphi process that included a literature review in PubMed and Embase, followed by interviews with experts, to quantify the historical epidemiology of HBV infection. We then used a dynamic HBV transmission and progression model to estimate the country-level and regional-level prevalence of HBsAg in 2016 and the effect of prophylaxis and treatment on disease burden. FINDINGS: We developed models for 120 countries, 78 of which were populated with data approved by experts. Using these models, we estimated that the global prevalence of HBsAg in 2016 was 3·9% (95% uncertainty interval [UI] 3·4-4·6), corresponding to 291 992 000 (251 513 000-341 114 000) infections. Of these infections, around 29 million (10%) were diagnosed, and only 4·8 million (5%) of 94 million individuals eligible for treatment actually received antiviral therapy. Around 1·8 (1·6-2·2) million infections were in children aged 5 years, with a prevalence of 1·4% (1·2-1·6). We estimated that 87% of infants had received the three-dose HBV vaccination in the first year of life, 46% had received timely birth-dose vaccination, and 13% had received hepatitis B immunoglobulin along with the full vaccination regimen. Less than 1% of mothers with a high viral load had received antiviral therapy to reduce mother-to-child transmission. INTERPRETATION: Our estimate of HBV prevalence in 2016 differs from previous studies, potentially because we took into account the effect of infant prophylaxis and early childhood vaccination, as well as changing prevalence over time. Although some regions are well on their way to meeting prophylaxis and prevalence targets, all regions must substantially scale-up access to diagnosis and treatment to meet the global targets. FUNDING: John C Martin Foundation.status: publishe

Global change in hepatitis C virus prevalence and cascade of care between 2015 and 2020: a modelling study

Background Since the release of the first global hepatitis elimination targets in 2016, and until the COVID-19 pandemic started in early 2020, many countries and territories were making progress toward hepatitis C virus (HCV) elimination. This study aims to evaluate HCV burden in 2020, and forecast HCV burden by 2030 given current trends. Methods This analysis includes a literature review, Delphi process, and mathematical modelling to estimate HCV prevalence (viraemic infection, defined as HCV RNA-positive cases) and the cascade of care among people of all ages (age ≥0 years from birth) for the period between Jan 1, 2015, and Dec 31, 2030. Epidemiological data were collected from published sources and grey literature (including government reports and personal communications) and were validated among country and territory experts. A Markov model was used to forecast disease burden and cascade of care from 1950 to 2050 for countries and territories with data. Model outcomes were extracted from 2015 to 2030 to calculate population-weighted regional averages, which were used for countries or territories without data. Regional and global estimates of HCV prevalence, cascade of care, and disease burden were calculated based on 235 countries and territories. Findings Models were built for 110 countries or territories: 83 were approved by local experts and 27 were based on published data alone. Using data from these models, plus population-weighted regional averages for countries and territories without models (n=125), we estimated a global prevalence of viraemic HCV infection of 0·7% (95% UI 0·7–0·9), corresponding to 56·8 million (95% UI 55·2–67·8) infections, on Jan 1, 2020. This number represents a decrease of 6·8 million viraemic infections from a 2015 (beginning of year) prevalence estimate of 63·6 million (61·8–75·8) infections (0·9% [0·8–1·0] prevalence). By the end of 2020, an estimated 12·9 million (12·5–15·4) people were living with a diagnosed viraemic infection. In 2020, an estimated 641000 (623000–765000) patients initiated treatment. Interpretation At the beginning of 2020, there were an estimated 56·8 million viraemic HCV infections globally. Although this number represents a decrease from 2015, our forecasts suggest we are not currently on track to achieve global elimination targets by 2030. As countries recover from COVID-19, these findings can help refocus efforts aimed at HCV elimination

Global prevalence, treatment, and prevention of hepatitis B virus infection in 2016: a modelling study

Background: The 69th World Health Assembly approved the Global Health Sector Strategy to eliminate viral hepatitis by 2030. Although no virological cure exists for hepatitis B virus (HBV) infection, existing therapies to control viral replication and prophylaxis to minimise mother-to-child transmission make elimination of HBV feasible. We aimed to estimate the national, regional, and global prevalence of HBsAg in the general population and in the population aged 5 years in 2016, as well as coverage of prophylaxis, diagnosis, and treatment. Methods: In this modelling study, we used a Delphi process that included a literature review in PubMed and Embase, followed by interviews with experts, to quantify the historical epidemiology of HBV infection. We then used a dynamic HBV transmission and progression model to estimate the country-level and regional-level prevalence of HBsAg in 2016 and the effect of prophylaxis and treatment on disease burden. Findings: We developed models for 120 countries, 78 of which were populated with data approved by experts. Using these models, we estimated that the global prevalence of HBsAg in 2016 was 3·9% (95% uncertainty interval [UI] 3·4–4·6), corresponding to 291 992 000 (251 513 000–341 114 000) infections. Of these infections, around 29 million (10%) were diagnosed, and only 4·8 million (5%) of 94 million individuals eligible for treatment actually received antiviral therapy. Around 1·8 (1·6–2·2) million infections were in children aged 5 years, with a prevalence of 1·4% (1·2–1·6). We estimated that 87% of infants had received the three-dose HBV vaccination in the first year of life, 46% had received timely birth-dose vaccination, and 13% had received hepatitis B immunoglobulin along with the full vaccination regimen. Less than 1% of mothers with a high viral load had received antiviral therapy to reduce mother-to-child transmission. Interpretation: Our estimate of HBV prevalence in 2016 differs from previous studies, potentially because we took into account the effect of infant prophylaxis and early childhood vaccination, as well as changing prevalence over time. Although some regions are well on their way to meeting prophylaxis and prevalence targets, all regions must substantially scale-up access to diagnosis and treatment to meet the global targets. Funding: John C Martin Foundation