Cost-effectiveness of hepatitis A vaccination for adults in China: A decision tree Markov model study

Although the hepatitis A vaccine has been introduced into in China's National Immunization Program for many years, an immunity gap persists among young adults, posing a continued risk of hepatitis A outbreaks. This study aimed to evaluate the cost-effectiveness of hepatitis A vaccination in adults (≥20 years).

We developed a decision tree Markov model to evaluate various hepatitis A vaccination strategies from a societal perspective, incorporating parameters derived from previously published data. The strategies included serological screening followed by vaccination of susceptible individuals, as well as vaccination without prior screening. Both live attenuated and inactivated vaccines were considered. The incremental cost-effectiveness ratio (ICER) of each strategy was calculated relative to the status quo (no vaccination). The robustness of the findings was assessed through one-way deterministic sensitivity analysis and probabilistic sensitivity analysis.

In a cohort of 100,000 individuals aged 20-78 years, the four vaccination strategies prevented 4024-4180 hepatitis A cases. Compared to no vaccination, all strategies were cost-saving at a willingness-to-pay threshold of one time China's per capita GDP, with incremental savings of $1584-$2733 per QALY gained. However, when applying standard incremental analysis to compare active strategies, screening followed by single-dose live attenuated hepatitis A vaccine (HepA-L) was the most cost-effective option compared to the previous non-dominated option. The two non-screening strategies were dominated by screening-based strategies. Results remained robust across sensitivity analyses.

Compared to the status quo (no vaccination), hepatitis A vaccination in Chinese adults is cost-saving, while pre-vaccination serological screening yields additional cost savings. Screening followed by administration of a single-dose of live attenuated hepatitis A vaccine (HepA-L) for the population aged 20-78 years was the most cost-saving strategy. Our findings offer evidence-based support for the future adjustment and optimization of immunization strategies for policymakers.