Maternal and Child Health Directorate, FMoH Ethiopia, P.O. Box 1234, Addis Ababa, Ethiopia.
Ethiopian Public Health Institute, FMoH. P.O. Box 1242, Addis Ababa, Ethiopia.
Pan Afr Med J. 2021 Dec 16;40:229. doi: 10.11604/pamj.2021.40.229.29028. eCollection 2021.
Ethiopia endorsed the African regional measles elimination goal in 2012 and has been implementing measles elimination strategies. Administration of measles vaccine before the age of nine months decreases seroconversion. Ensuring administration of valid doses and monitoring vaccine effectiveness is crucial for achieving measles elimination. The objective of the study was to describe the magnitude of invalid measles dose administration and vaccine effectiveness in Ethiopia.
we analysed the 2016 Ethiopian Demographic and Health Survey (EDHS) immunization coverage data for Ethiopia to determine the age at measles vaccine administration and proportion of measles age invalid doses administered. The national measles surveillance data for children with birthdates that match 12-23 months old children surveyed in the EDHS 2016, were analysed to determine the Proportion of Cases Vaccinated (PCV) with one dose of measles vaccine. We estimated the effectiveness of measles vaccine by using the proportion of measles cases vaccinated (PCV) from measles surveillance data and the measles vaccination coverage among children aged 12-23 months reported in the demographic health survey (DHS) done in 2016 (Percent of Population Vaccinated for measles, PPV). The screening method was used to estimate measles vaccine effectiveness at national level and for regions which reported more than 30 measles cases among children 9-23 months of age in the 2013-2015 period. The correlation between the median age of invalid doses administered, proportion of invalid doses and measles vaccine effectiveness was analysed.
at national level, the proportion of invalid measles dose administration was 27.6% for children aged 12-35 months surveyed in the 2016 DHS survey in Ethiopia. Among children reported in the measles case-based surveillance database with birthdates that match the children surveyed in the Ethiopian DHS 2016, the proportion of measles cases vaccinated with a single dose of measles vaccine in the 2013-2015 period was 22.7%. The vaccine effectiveness for single dose measles vaccination was estimated at 75.3%. The measles vaccine effectiveness was low for regions with high proportion of invalid dose administration and lower median age of invalid dose administration. The median age of measles dose administered before the age of nine months was significantly correlated with measles vaccine effectiveness (r=0.971, p=0.001) in the respective regions.
the proportion of invalid measles dose administration is very high in Ethiopia and is associated with lower vaccine effectiveness. Further assessment should be carried out to understand the underlying root causes for invalid dose administration, focusing on areas with high proportion of invalid measles doses. The national program should devise strategies to promote timely vaccination as per the national schedule, and to revaccinate those vaccinated before 9 months of age. The ministry of health should also strengthen the platform for immunization in the 2 year life, to ensure high routine immunization coverage with two doses of measles vaccine to achieve the measles elimination goal in Ethiopia.
埃塞俄比亚于 2012 年支持非洲区域消除麻疹目标，并一直在实施消除麻疹战略。在 9 个月之前接种麻疹疫苗会降低血清转化率。确保接种有效剂量并监测疫苗效力对于实现麻疹消除至关重要。本研究的目的是描述埃塞俄比亚无效麻疹剂量接种的规模和疫苗效力。
我们分析了 2016 年埃塞俄比亚人口与健康调查（EDHS）的免疫覆盖率数据，以确定麻疹疫苗接种的年龄和接种的麻疹年龄无效剂量比例。对国家麻疹监测数据进行了分析，这些数据来自与 2016 年 EDHS 中 12-23 个月大的儿童相匹配的儿童的出生日期，以确定一剂麻疹疫苗的接种比例（接种麻疹疫苗的病例比例，PCV）。我们使用麻疹监测数据中的麻疹病例接种比例（PCV）和 2016 年人口与健康调查（DHS）中报告的 12-23 个月大儿童的麻疹疫苗接种率（PPV）来估计麻疹疫苗的效力。采用筛查法估算全国和在 2013-2015 年间报告 9-23 个月大儿童麻疹病例超过 30 例的地区的麻疹疫苗效力。分析了无效麻疹剂量接种比例、无效剂量比例和麻疹疫苗效力之间的中位数年龄的相关性。
在国家一级，2016 年埃塞俄比亚 DHS 调查中 12-35 个月大的儿童中，无效麻疹剂量接种比例为 27.6%。在与 2016 年埃塞俄比亚 DHS 中调查的儿童出生日期相匹配的基于麻疹病例的监测数据库中，2013-2015 年间，一剂麻疹疫苗接种的麻疹病例比例为 22.7%。单剂麻疹疫苗接种的疫苗效力估计为 75.3%。在无效剂量接种比例较高和无效剂量接种中位数年龄较低的地区，麻疹疫苗效力较低。在各自地区，麻疹剂量接种前 9 个月内的中位数年龄与麻疹疫苗效力呈显著相关（r=0.971，p=0.001）。
埃塞俄比亚无效麻疹剂量接种比例非常高，与疫苗效力较低有关。应进一步评估，以了解无效剂量接种的根本原因，重点关注无效麻疹剂量比例较高的地区。国家方案应制定战略，按国家计划及时接种疫苗，并对 9 个月前接种疫苗的人群进行复种。卫生部还应加强两年生命中的免疫平台，以确保高常规免疫覆盖率，接种两剂麻疹疫苗，实现埃塞俄比亚的麻疹消除目标。
