Economic evaluation of alternative PCV13 vaccination strategies in Guangxi, China: a decision tree-Markov model study.
BACKGROUND Pneumococcal disease remains a major cause of morbidity and mortality among children under five years of age, particularly in settings with low vaccine coverage. In China, the 13-valent pneumococcal conjugate vaccine (PCV13) is not included in the National Immunization Program (NIP), resulting in suboptimal uptake. This study evaluated the health and economic impact of including PCV13 in the immunization program in Guangxi Zhuang Autonomous Region. METHODS A decision tree-Markov model was used to simulate a birth cohort of 420,000 children over a 5-year horizon from a societal perspective. The current self-paid vaccination strategy was compared with NIP inclusion. Outcomes included costs, cases, deaths, quality-adjusted life years (QALYs), incremental cost-effectiveness ratios (ICERs), and benefit-cost ratios (BCRs). Costs and outcomes were discounted at 3%. One-way and probabilistic sensitivity analyses were conducted. RESULTS NIP inclusion increased vaccination coverage from 5900 to 417,019 children and was projected to prevent 77,042 cases and 327 deaths over 5 years. Despite higher vaccination costs, reduced disease burden resulted in a net economic benefit of USD 3.92 million (BCR: 1.03). The program generated an additional 25,702.2 QALYs, with an ICER of USD 6042.75 per QALY gained, below the per capita GDP threshold. Probabilistic sensitivity analysis showed that most simulations were below the willingness-to-pay threshold, with the probability of cost-effectiveness approaching 100%. CONCLUSIONS Including PCV13 in Guangxi's immunization program is highly cost-effective and likely to yield positive economic returns. These findings are robust and support policy decisions on PCV13 inclusion.