Optimization of Elderly Influenza and Pneumococcal Immunization Programs in Beijing, China Using Health Economic Evaluations: A Modeling Study

Abstract

(1) Background: Currently, residents ≥ 60 and ≥65 years old in Beijing, China, are eligible for free influenza and pneumococcal polysaccharide vaccines (PPSV23), respectively. The present study aimed to assess the cost-effectiveness of current and alternative strategies of dual influenza and PPSV23 vaccination among the elderly in Beijing. (2) Methods: We developed a Markov state-transition model to compare the costs and the quality-adjusted life years (QALYs) associated with four influenza and PPSV23 vaccination strategies among the elderly in Beijing. The strategies were as follows: (1) no vaccination; (2) only flu vaccine for people ≥ 60 years old; (3) flu vaccine for people ≥ 60 years old and PPSV23 for people ≥ 65 years old; and (4) dual influenza vaccines and PPSV23 for people ≥ 60 years old. Incremental costs and QALYs were quantified to determine the optimal option. If dominant strategies emerged, the Chinese gross domestic product per capita in 2021 (80,976 CNY) was used as the willingness-to-pay (WTP) threshold to covert QALYs into the monetary equivalent. (3) Results: The current program saved costs and increased QALYs compared to no vaccination or flu vaccine-only strategies. However, extending free PPSV23 to people ≥ 60 years old saved 0.35 CNY additionally while increasing QALYs marginally compared with the current policy. Results were robust in all sensitivity analyses. (4) Conclusion: Beijing's current dual influenza and pneumococcal vaccination program was cost-effective among the elderly compared with the preceding policies of no vaccination and flu-only immunization programs. However, the program can further save money while enhancing the population health by extending PPSV23 to all people ≥ 60 years old.

Keywords: cost-effectiveness; influenza; pneumococcal; vaccine.

Figure 1

The structure of the Markov model. IPD, invasive pneumococcal disease.

Figure 2

The NMB changes of strategy 4 compared with those of the current policy (strategy 3) in OWSA. PPSV23, pneumococcal polysaccharide vaccines; IPD, invasive pneumococcal disease; VE, vaccine effectiveness; YO, years old.

Figure 3

The scatterplots of QALYs against costs associated with the four strategies from the PSA. QALY, quality-adjusted life year; YO, years old.