Aljohani Basim, Hall Randolph
Department of Industrial and Systems Engineering, University of Florida, Gainesville, FL 32603, USA.
Epstein Department of Industrial and Systems Engineering, University of Southern California, Los Angeles, CA 90089, USA.
Int J Environ Res Public Health. 2024 Apr 17;21(4):491. doi: 10.3390/ijerph21040491.
In the early phases of the COVID-19 pandemic, vaccine accessibility was limited, impacting large metropolitan areas such as Los Angeles County, which has over 10 million residents but only nine initial vaccination sites, which resulted in people experiencing long travel times to get vaccinated. We developed a mixed-integer linear model to optimize site selection, considering equitable access for vulnerable populations. Analyzing 277 zip codes between December 2020 and May 2021, our model incorporated factors such as car ownership, ethnic group disease vulnerability, and the Healthy Places Index, alongside travel times by car and public transit. Our optimized model significantly outperformed actual site allocations for all ethnic groups. We observed that White populations faced longer travel times, likely due to their residences being in more remote, less densely populated areas. Conversely, areas with higher Latino and Black populations, often closer to the city center, benefited from shorter travel times in our model. However, those without cars experienced greater disadvantages. While having many vaccination sites might improve access for those dependent on public transit, that advantage is diminished if people must search among many sites to find a location with available vaccines.
在新冠疫情的早期阶段，疫苗的可及性有限，这对诸如洛杉矶县这样的大型都市地区产生了影响。洛杉矶县有超过1000万居民，但最初只有9个疫苗接种点，这导致人们为了接种疫苗需要长途跋涉。我们开发了一个混合整数线性模型来优化接种点的选址，同时考虑弱势群体的公平可及性。在分析2020年12月至2021年5月期间的277个邮政编码区域时，我们的模型纳入了诸如汽车拥有情况、种族群体疾病易感性以及健康场所指数等因素，同时还考虑了驾车和乘坐公共交通的出行时间。我们优化后的模型在所有种族群体中显著优于实际的接种点分配情况。我们观察到，白人面临更长的出行时间，这可能是因为他们居住在更偏远、人口密度更低的地区。相反，拉丁裔和黑人人口较多的地区，通常更靠近市中心，在我们的模型中受益于较短的出行时间。然而，那些没有汽车的人处于更不利的地位。虽然设置许多接种点可能会改善依赖公共交通者的可及性，但如果人们必须在众多接种点中寻找有可用疫苗的地点，这种优势就会减弱。
