Cost-effectiveness of continuing pneumococcal conjugate vaccination at age 65 in the context of indirect effects from the childhood immunization program.

Abstract The findings and conclusions in this report are those of the authors and do not necessarily represent the official positon of the Centers for Disease Control and Prevention. Background Continued indirect effects provided by the childhood pneumococcal conjugate vaccine (13-valent pneumococcal conjugate vaccine [PCV13]) program in the United States have decreased disease in the adult population, reducing the potential direct effects of vaccinating older adults. Objective We examined the incremental cost-effectiveness of continuing to recommend PCV13 in series with 23-valent pneumococcal polysaccharide vaccine (PPSV23) at age 65 compared to a strategy that only included a recommendation for PPSV23 at age 65. Methods We used a probabilistic model following a cohort of 65 year olds in 2019. We used vaccination coverage and disease incidence estimates for healthy adults and adults with chronic medical conditions. We incorporated continued indirect effects from the childhood PCV13 program on adult disease incidence. Results In the base case scenario, continuing to recommend PCV13 at age 65 cost $561,682 per quality-adjusted life year (QALY) gained. In a scenario where PPSV23 provided modest protection against non-invasive pneumococcal pneumonia, costs increased to $2.3 million per QALY. These estimates are larger than our prior estimates for cost-effectiveness of this recommendation in the context of predicted indirect effects due to new data indicating PCV13 provided limited impact on serotype 3, the major cause of the remaining PCV13-type disease. Under our prior assumptions about PCV13 effectiveness against serotype 3 disease, the cost of continuing the recommendation is $207,607 per QALY. Conclusion Indirect effects from the childhood PCV13 program have dramatically increased the cost per QALY of continuing to recommend PCV13 at age 65 after only a few years.