Health impact and economic evaluation of expanded program on immunization in China from 1974 to 2024: a modelling study
Wang C., Lai X., Abbas K., Pouwels K., Zhang H., Jit M., Fang H.
Background: The Expanded Program on Immunization (EPI), initiated by the WHO in 1974, is a cornerstone of global public health. Today, China’s EPI covers over one-sixth of the world’s population and encompasses eight routine vaccines with high coverage rates. Methods: This study aimed to estimate health and economic impacts of China’s EPI against eight pathogens: measles, pertussis, hepatitis B, tuberculosis, hepatitis A, Japanese encephalitis, meningitis A, and poliomyelitis in 1974-2024. Health and economic outcomes were determined using mathematical models between a counterfactual scenario without vaccination and the current vaccination scenario, based on both calendar year and birth cohort approaches. Findings: We estimated that China’s EPI averted 703.02 million cases (95% credible interval: 699.51-722.80) and 2.48 million deaths (2.14-2.97) in 1974-2024 based on the calendar year approach, equivalent to a reduction of 160.22 million DALYs (145.05-196.99). Using the birth cohort approach, we predicted 707.41 million cases (703.93-727.03) and 7.01 million deaths (6.95-7.87) averted over the lifetime, resulting in a reduction of 279.02 million DALYs (265.78-316.12). From a societal perspective, the aggregated costs were USD 124.06 billion (120.49- 127.49), while the benefits amounted to USD 2417.85 billion (2359.38- 2710.35). China’s EPI yielded an aggregate benefit-cost ratio of 19.48 (18.82-22.08) from the societal perspective and 8.02 (7.64-8.80) from the provider’s perspective. Interpretation: China’s EPI has demonstrated remarkable health and economic achievements, contributing to worldwide EPI success over the past 50 years. Further investment in EPI is warranted to sustain coverage and expand vaccine inclusion in China and globally. Funding: Natural Science Foundation of Beijing Municipality.