Cost-effectiveness of community-based screening and treatment for chronic hepatitis B in The Gambia: an economic modelling analysis

Background: Despite the high burden of hepatitis B virus (HBV) infection in sub-Saharan Africa (SSA), a lack of access to widespread screening or treatment leads to most people remaining undiagnosed until later stages of disease when prognosis is poor and treatment options are limited. We evaluated the cost-effectiveness of community-based screening and early treatment with antiviral therapy for HBV in The Gambia. Methods: An economic evaluation comparing adult community-based screening using a Hepatitis B surface antigen (HBsAg) rapid test and subsequent HBV antiviral therapy to a status quo scenario, where no treatment is available, was performed by combining a decision tree with a Markov state transition model. This was parameterised with primary screening and cost data from the PROLIFICA study. A health provider perspective was taken and costs and health outcomes were discounted at 3% per annum. Findings: In The Gambia, where the HBsAg prevalence is 8.8% among those aged over 30 years old, adult screening and treatment for HBV, has an Incremental Cost-Effectiveness Ratio (ICER) of $540 per Disability Adjusted Life Year (DALY) averted, $645 per Life Year (LY) saved and $511 per Quality Adjusted Life Year (QALY) gained, compared to status quo. These ICERs are in line with willingness-to-pay levels of one times the country's Gross Domestic Product (GDP) per capita ($487) per DALY averted, whilst remaining robust, over a wide range of epidemiological and cost parameters. Interpretation: Adult community-based screening and treatment for HBV in the Gambia is likely to be a cost-effective intervention with an ICER that is comparable with those of HIV screening and treatment interventions in SSA. Even higher cost-effectiveness, may be achievable with targeted facility-based screening, price reductions of drug and diagnostics and integration of HBV screening with other public health interventions