Public Health Informatics, Computational, and Operations Research (PHICOR), CUNY Graduate School of Public Health & Health Policy, New York City, New York.
National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas; Department of Pediatrics, Baylor College of Medicine, Houston, Texas; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas.
Am J Prev Med. 2021 May;60(5):605-613. doi: 10.1016/j.amepre.2021.01.001. Epub 2021 Jan 19.
During a pandemic, there are many situations in which the first available vaccines may not have as high effectiveness as vaccines that are still under development or vaccines that are not yet ready for distribution, raising the question of whether it is better to go with what is available now or wait.
In 2020, the team developed a computational model that represents the U.S. population, COVID-19 coronavirus spread, and vaccines with different possible efficacies (to prevent infection or to reduce severe disease) and vaccination timings to estimate the clinical and economic value of vaccination.
Except for a limited number of situations, mainly early on in a pandemic and for a vaccine that prevents infection, when an initial vaccine is available, waiting for a vaccine with a higher efficacy results in additional hospitalizations and costs over the course of the pandemic. For example, if a vaccine with a 50% efficacy in preventing infection becomes available when 10% of the population has already been infected, waiting until 40% of the population are infected for a vaccine with 80% efficacy in preventing infection results in 15.6 million additional cases and 1.5 million additional hospitalizations, costing $20.6 billion more in direct medical costs and $12.4 billion more in productivity losses.
This study shows that there are relatively few situations in which it is worth foregoing the first COVID-19 vaccine available in favor of a vaccine that becomes available later on in the pandemic even if the latter vaccine has a substantially higher efficacy.
在大流行期间,可能会出现许多情况,即首批可用疫苗的有效性可能不如仍在开发中的疫苗或尚未准备好分发的疫苗高,这就提出了一个问题,即是否最好选择现有的疫苗,还是等待。
在 2020 年,该团队开发了一种计算模型,该模型代表了美国人口、COVID-19 冠状病毒的传播以及具有不同可能疗效(预防感染或减轻严重疾病)和不同接种时间的疫苗,以估计疫苗接种的临床和经济价值。
除了少数情况外,主要是在大流行早期和预防感染的疫苗,当有初始疫苗可用时,等待疗效更高的疫苗会导致大流行期间的住院和费用增加。例如,如果一种预防感染的疫苗的有效性为 50%,而 10%的人口已经感染,那么等到 40%的人口感染预防感染的疫苗的有效性为 80%,则会导致 1560 万例额外病例和 150 万例额外住院治疗,直接医疗费用增加 206 亿美元,生产力损失增加 124 亿美元。
本研究表明,在大流行后期出现的疫苗具有明显更高的疗效的情况下,放弃首批可用的 COVID-19 疫苗转而选择后者的情况相对较少。