A cost-benefit analysis of adult immunization programs across ten countries: Modeling the socioeconomic value of immunization for older populations compared to no vaccination.

Globally aging demographics necessitate proactive public health interventions like adult immunization programs, but comprehensive estimates of their socioeconomic value are lacking or narrow in perspective, risking suboptimal decision-making. To estimate the socioeconomic value of adult immunization programs for influenza, pneumococcal disease, herpes zoster, and respiratory syncytial virus across ten countries. Benefit-cost analysis using static disease models and a reference case framework to quantify net monetary benefits of immunization programs using different monetization approaches for non-monetary benefits. Australia, Brazil, France, Germany, Italy, Japan, Poland, South Africa, Thailand, US. Based on the lowest and highest valuations of non-monetary benefits, across all immunization programs, the mean benefit-cost ratios (BCRs) ranged from 5 to 19, suggesting substantial positive returns. Mortality-focused disease programs like influenza (BCRs 6-22) and pneumococcal disease (BCRs 15-33) showed the highest returns. The emerging respiratory syncytial virus program also demonstrated high potential positive returns (BCRs 6-16). Herpes zoster programs which primarily affect quality of life also yielded positive returns with BCRs of 2-4. Across all data points, 95% of estimated BCRs exceeded the cost-neutral 1.0 threshold. Adult immunization programs for influenza, pneumococcal disease, respiratory syncytial virus and herpes zoster consistently show positive returns on investment across a diversity of countries. Funding these programs provides long-term benefits and may help to mitigate upcoming global demographic challenges.