Health economic evaluation of immunization strategies of hepatitis E vaccine for elderly population.

Objective This study was conducted to assess the cost-effectiveness of hepatitis E vaccination of elderly population in the sporadic regions in China. Methods We used a decision tree-Markov model to evaluate the cost-effectiveness of 3 kinds of hepatitis E virus vaccination strategies from societal perspectives. Parameter estimates were obtained from published researches and experts' opinion. The time horizon was 16 years, and the discounted rate was 3% annually. Costs are expressed in 2016 US dollars. Results The universal vaccination strategy had an incremental cost-effectiveness ratio (ICER) of US$ 8475.90 per QALY gained versus no vaccination. The implementation of screening and vaccination strategy would have an ICER of US$ 4044.28, compared with no vaccination. The vaccination was cost-effective (ICER< 3 times China's per capital gross domestic product/quality-adjusted life years). The QALY of asymptomatic infection, vaccine coverage and vaccine protection are the important parameters impacting the ICER in one-way sensitivity analysis and screening and vaccination being the dominant strategy in probabilistic sensitivity analysis. Conclusion This analysis indicates that screening and vaccination is the most cost-effective hepatitis E intervention strategy of elderly population in sporadic region in China.