Modeling Progress Toward Elimination of Hepatitis B in Australia

Chronic hepatitis B (CHB) is a significant global health concern, and the most prevalent blood-borne virus in Australia. World Health Organization (WHO) member states have committed to global elimination, with targets to diagnose 90% of people living with CHB, treat 80% of those eligible, and reduce attributable deaths by 65% by the year 2030. Australia has committed to national targets of 80% diagnosed, 20% on treatment, and a 30% reduction in deaths by 2022.

We constructed and implemented a mathematical model to estimate the burden of CHB incorporating vaccination, phases of infection, cirrhosis progression, and mortality attributed to decompensated cirrhosis and hepatocellular carcinoma and examined the population-level impact of antiviral therapy. Diversity was integrated according to migration patterns, CHB prevalence by country of birth, Indigenous status, and age. Modelled outcomes were subjected to multivariate uncertainty analysis. Of the estimated 221,420 people living with CHB in Australia in 2017, 68% were diagnosed and 8.7% were receiving treatment (less than one-third of those estimated to be eligible). Based on current trends, the proportion of people living with CHB who have been diagnosed will reach 71% by 2022 and 81% by 2030, and treatment uptake will rise to 11.2% by 2022 and 12.9% by 2030, resulting in a 5.7% reduction in CHB-attributable deaths from 2015 to 2030. CHB treatment has prevented approximately 2,300 deaths in Australia between 2000 and 2017.

Australia is not on track to meet local and global targets regarding CHB. Comprehensive and regularly updated modelling approaches accounting for diversity within the population are a useful tool to measure progress and impact of interventions, and quantify further improvements required to meet elimination goals.