Maternal & Child Health, IRD Pakistan, 4th Floor Woodcraft Building, Korangi Creek, Karachi 75190, Pakistan.
IRD Global, 16 Raffles Quay, #16-02, Hong Leong Building, Singapore 048581, Singapore.
Vaccine. 2023 May 2;41(18):2922-2931. doi: 10.1016/j.vaccine.2023.03.051. Epub 2023 Apr 1.
Despite the potential of geospatial technologies to track and monitor coverage, they are underutilized for guiding immunization program strategy and implementation, especially in low-and-middle-income countries. We conducted geospatial analysis to explore the geographic and temporal trends of immunization coverage, and examined the pattern of immunization service access (outreach and facility based) by children.
We extracted data to analyze coverage rates across different dimensions (by enrolment year, birth year and vaccination year) from 2018 till 2020 in Karachi, Pakistan using the Sindh Electronic Immunization Registry (SEIR). We conducted geospatial analysis to assess variation in coverage rates of BCG, Pentavalent (Penta)-1, Penta-3, and Measles-1 vaccines using Government targets. We also analyzed the proportion of children receiving their routine vaccinations at fixed centers and outreach and examined whether children received vaccinations at the same or multiple immunization centers.
A total of 1,298,555 children were born, enrolled or vaccinated from 2018 till 2020. At the district level, analysis by enrollment and birth year showed coverage increased between 2018 and 2019 and declined in 2020, while analysis by vaccination year showed consistent increase in coverage. However, micro-geographic analysis revealed pockets where coverage persistently declined. Notably 27/168, 39/168 and 3/156 Union councils showed consistently declining coverage when analyzing by enrollment, birth and vaccination year respectively. More than half (52.2%, 678,280/1,298,555) of the children received all their vaccinations exclusively through fixed centers and, 71.7% (499,391/696,701) received all vaccinations from the same centers.
Despite overall improving vaccination coverage between 2018 and 2020, certain geographic areas have consistently declining coverage rates, which is detrimental for equity. Making immunization inequities visible through geospatial analysis is the first step to ensure resources are allocated optimally. Our study provides impetus for immunization programs to develop and invest in geospatial technologies, harnessing its potential for improved coverage and equity.
尽管地理空间技术有可能跟踪和监测覆盖范围，但它们在指导免疫规划战略和实施方面的应用不足，尤其是在中低收入国家。我们进行了地理空间分析，以探讨免疫覆盖范围的地理和时间趋势，并检查了儿童获得免疫服务（外展和设施）的模式。
我们从巴基斯坦卡拉奇的 2018 年到 2020 年的 Sindh 电子免疫登记处（SEIR）中提取数据，分析了不同维度（按入学年份、出生年份和接种年份）的覆盖率。我们进行了地理空间分析，以评估 BCG、五价疫苗-1、五价疫苗-3 和麻疹疫苗-1 疫苗的覆盖率变化情况，使用政府目标作为评估标准。我们还分析了在固定中心和外展中接受常规疫苗接种的儿童比例，并检查了儿童是否在同一或多个免疫中心接种疫苗。
2018 年至 2020 年期间，共有 1,298,555 名儿童出生、入学或接种疫苗。在地区一级，按入学和出生年份进行的分析表明，2018 年至 2019 年覆盖范围增加，2020 年下降，而按接种年份进行的分析则显示覆盖范围持续增加。然而，微观地理分析显示，一些地区的覆盖范围持续下降。值得注意的是，在按入学、出生和接种年份进行分析时，分别有 27/168、39/168 和 3/156 个联盟委员会的覆盖范围持续下降。超过一半（52.2%，678,280/1,298,555）的儿童仅通过固定中心接受所有疫苗接种，71.7%（499,391/696,701）从同一中心接受所有疫苗接种。
尽管 2018 年至 2020 年期间总体上免疫接种覆盖率有所提高，但某些地理区域的覆盖率持续下降，这不利于公平性。通过地理空间分析使免疫不平等现象可见是确保资源得到最佳分配的第一步。我们的研究为免疫规划提供了动力，以开发和投资地理空间技术，利用其提高覆盖率和公平性的潜力。
