Cost-Effectiveness of a 5-Year Free Influenza Vaccination Program for Older Adults in Eastern China: Real-World...

Older adults shoulder the greatest influenza burden, yet vaccination coverage in China remains low, especially in rural counties. Using community data from Deqing County, Zhejiang (2018-2022), we built a decision tree-Markov model with 2-week cycles to evaluate a five-year free vaccination program for older adults under the current policy for residents aged ≥60 years and in two additional subgroup-based scenario analyses, one restricted to adults aged ≥70 years and the other to older adults with chronic diseases. From health care and societal perspectives, incremental cost-effectiveness ratios (ICERs) for the current program were US$10 535 and US$9657 per quality-adjusted life-year, respectively, both below the willingness-to-pay threshold of 1.5× local per capita Gross Domestic Product (GDP) (US$25 887). In subgroup-based scenario analyses, the policy showed greater cost-effectiveness and larger reductions in severe influenza when evaluated in the oldest old and in older adults with chronic conditions. Because decisions are anchored to locally scaled thresholds and routine data, findings may provide policy-relevant evidence for similar county- and district-level settings, although transferability should be interpreted with caution.