Hepatitis B in Africa Collaborative Network: cohort profile and analysis of baseline data (original) (raw)

An Insight into the Epidemiology and Genetic Diversity of Hepatitis B Virus in Africa

Journal of Molecular Virology and Immunology

Hepatitis viruses (hepatotropic viruses) are classified into five ‎kinds, denoted by the letters A, B, C, D, and E, each with its ‎own unique genotypes, clinical implications, and geographic ‎distribution. Viral hepatitis is a type of liver inflammation that ‎can resolve on its own or proceed to cirrhosis or hepatocellular ‎cancer. Hepatitis A, B, and C infections are the most common ‎types of infectious viral hepatitis. Over the previous five ‎decades, hepatitis B virus (HBV) infection has exhibited an ‎intermediate or high endemicity level in low-income nations. ‎HBV genotype variation is thought to be crucial in regulating ‎disease development, infection outcome, antiviral therapy ‎response, and illness prognosis. HBV is divided into ten ‎genotypes (A-J) and roughly 40 sub-genotypes, correlated with ‎different geographic distributions, transmission routes, and ‎disease progression. The goal of this study was to figure out ‎the current status of HBV prevalence and genotype distrib...

Hepatitis B in sub-Saharan Africa: strategies to achieve the 2030 elimination targets

The lancet. Gastroenterology & hepatology, 2017

The WHO global health sector strategy on viral hepatitis, created in May, 2016, aims to achieve a 90% reduction in new cases of chronic hepatitis B and C and a 65% reduction in mortality due to hepatitis B and C by 2030. Hepatitis B virus (HBV) is endemic in sub-Saharan Africa, and despite the introduction of universal hepatitis B vaccination and effective antiviral therapy, the estimated overall seroprevalence of hepatitis B surface antigen remains high at 6·1% (95% uncertainty interval 4·6-8·5). In this Series paper, we have reviewed the literature to examine the epidemiology, burden of liver disease, and elimination strategies of hepatitis B in sub-Saharan Africa. This paper reflects a supranational perspective of sub-Saharan Africa, and recommends several priority elimination strategies that address the need both to prevent new infections and to diagnose and treat chronic infections. The key to achieving these elimination goals in sub-Saharan Africa is the effective prevention o...

Hepatitis B in sub‐Saharan Africa—How many patients need therapy?

Journal of Viral Hepatitis, 2019

Hepatitis B is endemic in sub‐Saharan Africa with ~60 million people chronically infected. While prevention, through vaccination, is central to elimination strategies, only 11 countries have birth dose vaccination and full vaccine coverage remains at suboptimal levels. Furthermore, to fully realize elimination, those chronically infected need to be identified, assessed for therapy and then linked to care. Given current treatment criteria, the precise quantum of people warranting therapy, according to criteria, is essentially unknown. The issue is further complicated by data to suggest differences in the numbers of people requiring treatment when applying WHO as compared to European Association for the Study of the Liver, EASL, criteria. Optimal determination of treatment eligibility is further hindered by the lack of available tools to adequately assess individual patients. It is conceivable that accurately determining the number of those requiring treatment, given the heterogeneity...

Prevalence and predictors of hepatitis B virus (HBV) infection in east Africa: evidence from a systematic review and meta-analysis of epidemiological studies published from 2005 to 2020

Archives of Public Health

Background The epidemiology of hepatitis B virus (HBV) in the general population in east Africa is not well documented. In this meta-analysis, we examined 37 full published research articles to synthesise up-to-date data on the prevalence and predictors of the HBV burden for the effective prevention and management of the virus in our region. Methods We examined 37 full published research articles found using PubMed, Scopus, African Journal Online (AJOL), and Google Scholar between May and October 2020. Dichotomous data on HBV prevalence and predictors of infection were extracted from the individual studies. The HBV prevalence, test of proportion, relative risk, and I2 statistics for heterogeneity were calculated using MedCalc software version 19.1.3. Begg’s tests was used to test for publication bias. Sources of heterogeneity were analysed through sensitivity analysis, meta-regression, and sub-group analysis at 95% CI. P 0.05). Omitting the study with the largest sample size slight...

Hepatitis B virus seroepidemiology data for Africa: Modelling intervention strategies based on a systematic review and meta- analysis

International Sustainable Development Goals (SDGs) for elimination of hepatitis B virus (HBV) infection set ambitious targets for 2030. In African populations, infant immunisation has been fundamental to reducing incident infections in children, but overall population prevalence of chronic hepatitis B (CHB) infection remains high. In high-prevalence populations, adult catch-up vaccination has sometimes been deployed, but an alternative Test and Treat (T&T) approach could be used as an intervention to interrupt transmission. Universal T&T has not been previously evaluated as a population intervention for HBV infection, despite high-profile data supporting its success with human immunodeficiency virus (HIV).

Early experiences from one of the first treatment programs for chronic hepatitis B in sub-Saharan Africa

BMC infectious diseases, 2017

Treatment for chronic hepatitis B (CHB) is virtually absent in sub-Saharan Africa. Here we present early experiences from a pilot program for treatment of CHB in Ethiopia. Adults (≥18 years) with CHB were included in a cohort study at St. Paul's Hospital Millennium Medical College, Addis Ababa, from February 2015. The baseline assessment included liver function tests, viral markers and transient elastography (Fibroscan 402, Echosense, France). Logistic regression models were used to identify predictors of fibrosis. Tenofovir disoproxil fumarate (TDF) was initiated based on the European Association for the Study of the Liver (EASL) criteria, with some modifications. The initial 300 patients underwent a more comprehensive evaluation and are presented here. One-hundred-and-thirty-eight patients (46.0%) were women and median age was 30 years (interquartile range 26-40). Co-infections were rare: four patients (1.3%) were anti-HCV positive, 11 (3.7%) were anti-HDV positive, whereas 5 ...

Mapping hepatitis B virus genotypes on the African continent from 1997 to 2021: a systematic review with meta-analysis

Scientific Reports

Hepatitis B virus (HBV) has ten genotypes (A–J) and over 40 sub-genotypes based on the divergence of ≥ 8% and 4 to < 8% in the complete genome respectively. These genotypes and sub-genotypes influence the disease prognosis, response to therapy and route of viral transmission. Besides, infection with mixed genotypes and recombinant genotypes has also been reported. This study aimed at mapping the de novo genotypes and correlate them with the immigration trends in order to inform future research on the underlying reasons for the relative distribution of HBV genotypes from a large sample size pooled from many primary studies. Data was extracted from 59 full research articles obtained from Scopus, PubMed, EMBASE, Willy library, African Journal Online (AJOL) and Google Scholar. Studies that investigated the genotypes, sub-genotypes, mixed genotypes and recombinant were included. The Z-test and regression were used for the analysis. The study protocol is registered with PROSPERO under ...

A new approach to prevent, diagnose, and treat hepatitis B in Africa

BMC Global and Public Health, 2023

There are 82 million people living with hepatitis B (PLWHB) in the World Health Organization Africa region, where it is the main cause of liver disease. Effective vaccines have been available for over 40 years, yet there are 990,000 new infections annually, due to limited implementation of hepatitis B birth dose vaccination and antenatal tenofovir prophylaxis for highly viraemic women, which could eliminate mother-to-child transmission. Despite effective and cheap antiviral treatment which can suppress hepatitis B virus replication and reduce the risk of hepatocellular carcinoma (HCC), < 2% of PLWHB are diagnosed, and only 0.1% are treated. As a result, PLWHB are frequently diagnosed only when they have already developed decompensated cirrhosis and late-stage HCC, and consequently 80,000 hepatitis B-associated deaths occur each year. Major barriers include complex treatment guidelines which were derived from high-income settings, lack of affordable diagnostics, lack or insufficient domestic funding for hepatitis care, and limited healthcare infrastructure. Current treatment criteria may overlook patients at risk of cirrhosis and HCC. Therefore, expanded and simplified treatment criteria are needed. We advocate for decentralized community treatment programmes, adapted for low-resource and rural settings with limited laboratory infrastructure. We propose a strategy of treat-all except patients fulfilling criteria that suggest low risk of disease progression. Expanded treatment represents a financial challenge requiring concerted action from policy makers, industry, and international donor agencies. It is crucial to accelerate hepatitis B elimination plans, integrate hepatitis B care into existing healthcare programmes, and prioritize longitudinal and implementation research to improve care for PLWHB.

Global, regional, and national burden of hepatitis B, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

Articles, 2022

Background Combating viral hepatitis is part of the UN Sustainable Development Goals (SDGs), and WHO has put forth hepatitis B elimination targets in its Global Health Sector Strategy on Viral Hepatitis (WHO-GHSS) and Interim Guidance for Country Validation of Viral Hepatitis Elimination (WHO Interim Guidance). We estimated the global, regional, and national prevalence of hepatitis B virus (HBV), as well as mortality and disability-adjusted life-years (DALYs) due to HBV, as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. This included estimates for 194 WHO member states, for which we compared our estimates to WHO elimination targets. Methods The primary data sources were population-based serosurveys, claims and hospital discharges, cancer registries, vital registration systems, and published case series. We estimated chronic HBV infection and the burden of HBV-related diseases, defined as an aggregate of cirrhosis due to hepatitis B, liver cancer due to hepatitis B, and acute hepatitis B. We used DisMod-MR 2.1, a Bayesian mixed-effects meta-regression tool, to estimate the prevalence of chronic HBV infection, cirrhosis, and aetiological proportions of cirrhosis. We used mortality-to-incidence ratios modelled with spatiotemporal Gaussian process regression to estimate the incidence of liver cancer. We used the Cause of Death Ensemble modelling (CODEm) model, a tool that selects models and covariates on the basis of out-ofsample performance, to estimate mortality due to cirrhosis, liver cancer, and acute hepatitis B. Findings In 2019, the estimated global, all-age prevalence of chronic HBV infection was 4•1% (95% uncertainty interval [UI] 3•7 to 4•5), corresponding to 316 million (284 to 351) infected people. There was a 31•3% (29•0 to 33•9) decline in all-age prevalence between 1990 and 2019, with a more marked decline of 76•8% (76•2 to 77•5) in prevalence in children younger than 5 years. HBV-related diseases resulted in 555 000 global deaths (487 000 to 630 000) in 2019. The number of HBV-related deaths increased between 1990 and 2019 (by 5•9% [-5•6 to 19•2]) and between 2015 and 2019 (by 2•9% [-5•9 to 11•3]). By contrast, all-age and age-standardised death rates due to HBV-related diseases decreased during these periods. We compared estimates for 2019 in 194 WHO locations to WHO-GHSS 2020 targets, and found that four countries achieved a 10% reduction in deaths, 15 countries achieved a 30% reduction in new cases, and 147 countries achieved a 1% prevalence in children younger than 5 years. As of 2019, 68 of 194 countries had already achieved the 2030 target proposed in WHO Interim Guidance of an all-age HBV-related death rate of four per 100 000. Interpretation The prevalence of chronic HBV infection declined over time, particularly in children younger than 5 years, since the introduction of hepatitis B vaccination. HBV-related death rates also decreased, but HBV-related death counts increased as a result of population growth, ageing, and cohort effects. By 2019, many countries had met the interim seroprevalence target for children younger than 5 years, but few countries had met the WHO-GHSS interim targets for deaths and new cases. Progress according to all indicators must be accelerated to meet 2030 targets, and there are marked disparities in burden and progress across the world. HBV interventions, such as vaccination, testing, and treatment, must be strategically supported and scaled up to achieve elimination. Funding Bill & Melinda Gates Foundation.