Background: Sustainable Development Goals set a challenge for the elimination of hepatitis B virus (HBV) infection\nas a public health concern by the year 2030. Deployment of a robust prophylactic vaccine and enhanced interventions\nfor prevention of mother to child transmission (PMTCT) are cornerstones of elimination strategy. However, in light of\nthe estimated global burden of 290 million cases, enhanced efforts are required to underpin optimisation of public\nhealth strategy. Robust analysis of population epidemiology is particularly crucial for populations in Africa made\nvulnerable by HIV co-infection, poverty, stigma and poor access to prevention, diagnosis and treatment.\nMethods: We here set out to evaluate the current and future role of HBV vaccination and PMTCT as tools for\nelimination. We first investigated the current impact of paediatric vaccination in a cohort of children with and\nwithout HIV infection in Kimberley, South Africa. Second, we used these data to inform a new parsimonious model\nto simulate the ongoing impact of preventive interventions. By applying these two approaches in parallel, we are able\nto determine both the current impact of interventions, and the future projected outcome of ongoing preventive\nstrategies over time.\nResults: Existing efforts have been successful in reducing paediatric prevalence of HBV infection in this setting to\n< 1%, demonstrating the success of the existing vaccine campaign. Our model predicts that, if consistently deployed,\ncombination efforts of vaccination and PMTCT can significantly reduce population prevalence (HBsAg) by 2030, such\nthat a major public health impact is possible even without achieving elimination. However, the prevalence of HBV\ne-antigen (HBeAg)-positive carriers will decline more slowly, representing a persistent population reservoir. We show\nthat HIV co-infection significantly reduces titres of vaccine-mediated antibody, but has a relatively minor role in\ninfluencing the projected time to elimination. Our model can also be applied to other settings in order to predict\nimpact and time to elimination based on specific interventions.\nConclusions: Through extensive deployment of preventive strategies for HBV, significant positive public health impact\nis possible, although time to HBV elimination as a public health concern is likely to be substantially longer than that\nproposed by current goals.
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