Wisdom Lake Academy of Pharmacy, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China.
Department of Biology, School of Science, Xi'an Jiaotong-Liverpool University, Suzhou, 215123, China.
BMC Public Health. 2022 Nov 19;22(1):2131. doi: 10.1186/s12889-022-14592-w.
Vaccination reduces the overall burden of COVID-19, while its allocation procedure may introduce additional health inequality, since populations characterized with certain social vulnerabilities have received less vaccination and been affected more by COVID-19. We used structural equation modeling to quantitatively evaluate the extent to which vaccination disparity would amplify health inequality, where it functioned as a mediator in the effect pathways from social vulnerabilities to COVID-19 mortality.
We used USA nationwide county (n = 3112, 99% of the total) level data during 2021 in an ecological study design. Theme-specific rankings of social vulnerability index published by CDC (latest data of 2018, including socioeconomic status, household composition & disability, minority status & language, and housing type & transportation) were the exposure variables. Vaccination coverage rate (VCR) during 2021 published by CDC was the mediator variable, while COVID-19 case fatality rate (CFR) during 2021 published by John Hopkinson University, the outcome variable.
Greater vulnerabilities in socioeconomic status, household composition & disability, and minority status & language were inversely associated with VCR, together explaining 11.3% of the variance of VCR. Greater vulnerabilities in socioeconomic status and household composition & disability were positively associated with CFR, while VCR was inversely associated with CFR, together explaining 10.4% of the variance of CFR. Our mediation analysis, based on the mid-year data (30 June 2021), found that 37.6% (mediation/total effect, 0.0014/0.0037), 10% (0.0003/0.0030) and 100% (0.0005/0.0005) of the effects in the pathways involving socioeconomic status, household composition & disability and minority status & language, respectively, were mediated by VCR. As a whole, the mediation effect significantly counted for 30.6% of COVID-19 CFR disparity. Such a mediation effect was seen throughout 2021, with proportions ranging from 12 to 32%.
Allocation of COVID-19 vaccination in the USA during 2021 led to additional inequality with respect to COVID-19 mortality. Viable public health interventions should be taken to guarantee an equitable deployment of healthcare recourses across different population groups.
疫苗接种降低了 COVID-19 的总体负担，但其分配程序可能会带来额外的健康不平等，因为某些社会弱势群体的人群接种疫苗较少，受 COVID-19 的影响更大。我们使用结构方程模型定量评估了疫苗接种差距在多大程度上会加剧健康不平等，因为它在社会脆弱性对 COVID-19 死亡率的影响途径中充当了中介。
我们在 2021 年期间使用了美国全国县（n=3112，占总数的 99%）的生态研究设计数据。暴露变量为疾病预防控制中心（CDC）发布的特定主题的社会脆弱性指数排名（最新数据为 2018 年，包括社会经济地位、家庭构成和残疾、少数族裔地位和语言以及住房类型和交通）。CDC 发布的 2021 年疫苗接种覆盖率（VCR）是中介变量，而约翰霍普金斯大学（John Hopkinson University）发布的 2021 年 COVID-19 病例死亡率（CFR）是结果变量。
社会经济地位、家庭构成和残疾以及少数民族地位和语言方面的脆弱性越大，与 VCR 呈负相关，共同解释了 VCR 变异的 11.3%。社会经济地位和家庭构成和残疾方面的脆弱性越大，与 CFR 呈正相关，而 VCR 与 CFR 呈负相关，共同解释了 CFR 变异的 10.4%。我们基于年中数据（2021 年 6 月 30 日）的中介分析发现，社会经济地位、家庭构成和残疾以及少数民族地位和语言这三个途径的影响中，分别有 37.6%（中介/总效应，0.0014/0.0037）、10%（0.0003/0.0030）和 100%（0.0005/0.0005）是由 VCR 介导的。总体而言，中介效应占 COVID-19 CFR 差异的 30.6%。这种中介效应在 2021 年全年都存在，比例从 12%到 32%不等。
2021 年美国 COVID-19 疫苗的分配导致 COVID-19 死亡率方面出现了额外的不平等。应采取可行的公共卫生干预措施，以确保医疗资源在不同人群中公平分配。
