Unlocking herpes zoster vaccination value in Spain: return on investment and actuarial model

BACKGROUND: Herpes zoster can cause long-lasting pain and productivity loss. Recombinant zoster vaccine (RZV) is included in the Spanish National Immunization Program (NIP) for 65-year-olds. This study estimated the societal benefit-cost ratio (BCR) of RZV in Spain. RESEARCH DESIGN AND METHODS: A cost-benefit analysis assessed the broader impacts of RZV over 50 years, using a disease model combined with actuarial projections (of population dynamics and labor force participation). The model incorporated age-specific vaccination cohorts, vaccination costs, healthcare resource use, quality-adjusted life-years (QALYs), mortality, and productivity. Productivity losses avoided were translated into gross domestic product (GDP) gains, and QALYs were monetized at 1xGDP/capita. A 20-year RZV program for 65-year-olds was modeled. Scenarios evaluated vaccination in working-age adults (50, 55, 60 years), and varied monetized QALY values. RESULTS: In the base case, reflecting the current NIP, vaccination of 65-year-olds generated 49,955 QALYs (€1,653.5 million, M), €899.0M healthcare costs avoided, and €354.0M GDP gains versus no vaccination. With an investment of €2,405.0M, the BCR was 1.21, indicating a positive return-on-investment. In scenarios, vaccinating working age 55- and 60-year-olds produced higher returns, from greater productivity gains (BCR 1.26). CONCLUSIONS: RZV in Spain provides a positive return-on-investment. Findings offer robust evidence for policymakers evaluating RZV.