Danish Institute for Advanced Study, University of Southern Denmark, Odense, Denmark.
Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
Front Public Health. 2022 Oct 5;10:967920. doi: 10.3389/fpubh.2022.967920. eCollection 2022.
Recent reviews summarize evidence that some vaccines have heterologous or non-specific effects (NSE), potentially offering protection against multiple pathogens. Numerous economic evaluations examine vaccines' pathogen-specific effects, but less than a handful focus on NSE. This paper addresses that gap by reporting economic evaluations of the NSE of oral polio vaccine (OPV) against under-five mortality and COVID-19.
We studied two settings: (1) reducing child mortality in a high-mortality setting (Guinea-Bissau) and (2) preventing COVID-19 in India. In the former, the intervention involves three annual campaigns in which children receive OPV incremental to routine immunization. In the latter, a susceptible-exposed-infectious-recovered model was developed to estimate the population benefits of two scenarios, in which OPV would be co-administered alongside COVID-19 vaccines. Incremental cost-effectiveness and benefit-cost ratios were modeled for ranges of intervention effectiveness estimates to supplement the headline numbers and account for heterogeneity and uncertainty.
For child mortality, headline cost-effectiveness was $650 per child death averted. For COVID-19, assuming OPV had 20% effectiveness, incremental cost per death averted was $23,000-65,000 if it were administered simultaneously with a COVID-19 vaccine <200 days into a wave of the epidemic. If the COVID-19 vaccine availability were delayed, the cost per averted death would decrease to $2600-6100. Estimated benefit-to-cost ratios vary but are consistently high.
Economic evaluation suggests the potential of OPV to efficiently reduce child mortality in high mortality environments. Likewise, within a broad range of assumed effect sizes, OPV (or another vaccine with NSE) could play an economically attractive role against COVID-19 in countries facing COVID-19 vaccine delays.
The contribution by DTJ was supported through grants from Trond Mohn Foundation (BFS2019MT02) and Norad (RAF-18/0009) through the Bergen Center for Ethics and Priority Setting.
最近的综述总结了一些疫苗具有异源或非特异性效应（NSE）的证据，这些效应可能为多种病原体提供保护。许多经济评估都考察了疫苗针对病原体的效应，但只有少数关注 NSE。本文通过报告口服脊髓灰质炎疫苗（OPV）针对 5 岁以下儿童死亡率和 COVID-19 的 NSE 的经济评估来填补这一空白。
我们研究了两种情况：（1）降低高死亡率环境下的儿童死亡率（几内亚比绍）和（2）预防印度的 COVID-19。在前一种情况下，干预措施包括每年进行三次疫苗接种运动，在此期间，儿童除常规免疫外还会额外接受 OPV。在后一种情况下，建立了易感-暴露-感染-恢复模型，以估计两种情况下 OPV 与 COVID-19 疫苗同时接种的人群效益。为了补充主要数字并考虑异质性和不确定性，我们针对干预效果估计的范围对增量成本效益比和效益成本比进行了建模。
对于儿童死亡率，每避免一例儿童死亡的成本效益为 650 美元。对于 COVID-19，如果 OPV 的有效性为 20%，那么如果在 COVID-19 疫苗接种后 200 天内的流行波中同时接种 OPV，每避免一例死亡的增量成本为 23000-65000 美元。如果 COVID-19 疫苗供应延迟，每避免一例死亡的成本将降至 2600-6100 美元。估计的效益成本比各不相同，但始终很高。
经济评估表明，OPV 有可能在高死亡率环境中有效地降低儿童死亡率。同样，在假设的效果大小的广泛范围内，OPV（或具有 NSE 的另一种疫苗）在面临 COVID-19 疫苗延迟的国家对抗 COVID-19 可能具有经济吸引力。
DTJ 的贡献得到了 Trond Mohn 基金会（BFS2019MT02）和挪威发展合作署（RAF-18/0009）通过卑尔根伦理和优先事项设置中心的资助。
