Mak Joshua, Odihi Deborah, Wonodi Chizoba, Ali Daniel, de Broucker Gatien, Sriudomporn Salin, Patenaude Bryan
International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
Vaccine X. 2023 Mar 16;14:100281. doi: 10.1016/j.jvacx.2023.100281. eCollection 2023 Aug.
Nigeria experiences wide heterogeneity in vaccination rates by vaccine and region. However, inequities in vaccination status extend beyond just geographic covariates. Traditionally, inequity is represented by a single metric pertaining to socioeconomic status. A growing body of literature suggests that this view is limiting, and a multi-factor approach is necessary to comprehensively evaluate relative disadvantage between individuals. The Vaccine Economics Research for Sustainability and Equity (VERSE) tool produces a composite equity metric, which accounts for multiple factors influencing inequity in vaccination coverage. We apply the VERSE tool to Nigeria's 2018 Demographic and Health Survey (DHS) to cross-sectionally evaluate equity in vaccination status for national immunization program (NIP) vaccines over the following contributing covariates: age of child, sex of child, maternal education level, socioeconomic status, health insurance status, state of residence, and urban or rural designation. We also assess equity for zero-dose, fully immunized for age, and completion of NIP. Results show that socioeconomic status contributes substantially to variation vaccination coverage, but it is not the most substantial factor. For all vaccination statuses, except for NIP completion, maternal education level is the greatest contributor towards a child's immunization status among model variables. We highlight the outputs for zero-dose, fully immunized at infancy, MCV1 and PENTA1. The percentage point gap in vaccination status between the top and bottom quintiles of disadvantage, as ranked by the composite indicator is 31.1 (29.5-32.7) for zero-dose status, 53.1 (51.3-54.9) for full immunization status, 48.9 (46.9-50.9) for MCV1, and 67.6 (66.0-69.2) for PENTA1. Though concentration indices indicate inequity for all statuses, full immunization coverage is very low at 31.5% suggesting significant gaps in reaching children after initial doses for routine immunizations. Applying the VERSE tool to future Nigeria DHS surveys can allow decisionmakers to track changes in vaccination coverage equity, in a standardized manner, over time.
尼日利亚在不同疫苗和地区的疫苗接种率方面存在很大差异。然而，疫苗接种状况的不平等不仅限于地理协变量。传统上，不平等由一个与社会经济地位相关的单一指标来表示。越来越多的文献表明，这种观点具有局限性，需要采用多因素方法来全面评估个体之间的相对劣势。疫苗可持续性与公平性经济研究（VERSE）工具产生了一个综合公平指标，该指标考虑了影响疫苗接种覆盖率不平等的多个因素。我们将VERSE工具应用于尼日利亚2018年人口与健康调查（DHS），以横断面方式评估国家免疫规划（NIP）疫苗在以下协变量方面的疫苗接种状况公平性：儿童年龄、儿童性别、母亲教育水平、社会经济地位、健康保险状况、居住州以及城乡划分。我们还评估了零剂次、按年龄完全免疫和完成NIP的公平性。结果表明，社会经济地位对疫苗接种覆盖率的差异有很大影响，但并非最主要因素。对于除NIP完成情况外的所有疫苗接种状况，在模型变量中，母亲教育水平对儿童免疫状况的影响最大。我们重点突出了零剂次、婴儿期完全免疫、MCV1和PENTA1的结果。根据综合指标排名，处于劣势的最高和最低五分位数之间的疫苗接种状况百分点差距，零剂次状况为31.1（29.5 - 32.7），完全免疫状况为53.1（51.3 - 54.9），MCV1为48.9（46.9 - 50.9），PENTA1为67.6（66.0 - 69.2）。尽管集中度指数表明所有状况都存在不平等，但完全免疫覆盖率非常低，仅为31.5%，这表明在常规免疫的初始剂次之后，在覆盖儿童方面存在显著差距。将VERSE工具应用于未来的尼日利亚DHS调查，可以使决策者以标准化方式跟踪疫苗接种覆盖率公平性随时间的变化。
