College of Information Science and Engineering, Northeastern University, Shenyang, Liaoning, China.
Front Public Health. 2023 Apr 24;11:1129183. doi: 10.3389/fpubh.2023.1129183. eCollection 2023.
The adequate vaccination is a promising solution to mitigate the enormous socio-economic costs of the ongoing COVID-19 pandemic and allow us to return to normal pre-pandemic activity patterns. However, the vaccine supply shortage will be inevitable during the early stage of the vaccine rollout. Public health authorities face a crucial challenge in allocating scarce vaccines to maximize the benefits of vaccination. In this paper, we study a multi-period two-dose vaccine allocation problem when the vaccine supply is highly limited. To address this problem, we constructed a novel age-structured compartmental model to capture COVID-19 transmission and formulated as a nonlinear programming (NLP) model to minimize the total number of deaths in the population. In the NLP model, we explicitly take into account the two-dose vaccination procedure and several important epidemiologic features of COVID-19, such as pre-symptomatic and asymptomatic transmission, as well as group heterogeneity in susceptibility, symptom rates, severity, etc. We validated the applicability of the proposed model using a real case of the 2021 COVID-19 vaccination campaign in the Midlands of England. We conducted comparative studies to demonstrate the superiority of our method. Our numerical results show that prioritizing the allocation of vaccine resources to older age groups is a robust strategy to prevent more subsequent deaths. In addition, we show that releasing more vaccine doses for first-dose recipients could lead to a greater vaccination benefit than holding back second doses. We also find that it is necessary to maintain appropriate non-pharmaceutical interventions (NPIs) during the vaccination rollout, especially in low-resource settings. Furthermore, our analysis indicates that starting vaccination as soon as possible is able to markedly alleviate the epidemic impact when the vaccine resources are limited but are currently available. Our model provides an effective tool to assist policymakers in developing adaptive COVID-19 likewise vaccination strategies for better preparedness against future pandemic threats.
充分的疫苗接种是减轻当前 COVID-19 大流行造成的巨大社会经济成本并使我们恢复大流行前正常活动模式的有希望的解决方案。然而，在疫苗推出的早期阶段，疫苗供应短缺将是不可避免的。公共卫生当局在分配稀缺疫苗以最大限度地提高疫苗接种效益方面面临着关键挑战。在本文中，我们研究了疫苗供应高度有限的多阶段两剂疫苗分配问题。为了解决这个问题，我们构建了一个新的年龄结构的分区模型来捕获 COVID-19 的传播，并将其制定为一个非线性规划 (NLP) 模型，以最大限度地减少人群中的总死亡人数。在 NLP 模型中，我们明确考虑了两剂疫苗接种程序和 COVID-19 的几个重要流行病学特征，例如无症状和症状前传播，以及对易感性、症状发生率、严重程度等的群体异质性。我们使用英格兰中部 2021 年 COVID-19 疫苗接种运动的实际案例验证了所提出模型的适用性。我们进行了比较研究，以证明我们方法的优越性。我们的数值结果表明，优先向年龄较大的人群分配疫苗资源是预防更多后续死亡的稳健策略。此外，我们还表明，为第一剂接种者释放更多疫苗剂量可能比保留第二剂疫苗剂量带来更大的疫苗接种效益。我们还发现，在疫苗推出期间，特别是在资源有限的情况下，有必要维持适当的非药物干预措施 (NPI)。此外，我们的分析表明，当疫苗资源有限但目前可用时，尽快开始接种疫苗能够显著减轻疫情的影响。我们的模型为决策者提供了一种有效的工具，以制定适应性 COVID-19 疫苗接种策略，为未来的大流行威胁做好更好的准备。
