Ketsela Admassu, Gebreyesus Seifu Hagos, Deressa Wakgari
Menelik II Medical & Health Sciences College, Kotebe Metropolitan University, Addis Ababa, Ethiopia.
Department of Nutrition and Dietetics, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia.
BMC Pediatr. 2021 May 10;21(1):226. doi: 10.1186/s12887-021-02690-4.
Immunization is essential to prevent between 2 and 3 million deaths globally each year and it is widely accepted that it is one of the most cost-effective health interventions. Despite all its advantages, immunization in Ethiopia is still far from the target set by the United Nations Sustainable Development Goals to achieve universal immunization by all countries in 2030. The 2016 Ethiopian Demographic and Health Survey (EDHS) reported an overall full immunization rate of only 38.3%. The objective of this study was to evaluate the spatial distribution of under immunization in 12 to 23 months old children and further identify the determinants of under immunization clustering in the Butajira Health and Demographic Surveillance Site (HDSS).
We conducted a community based sectional survey from March to April, 2016 in Butajira HDSS. We collected data on immunization status from a total of 482 children between the age of 12 to 23 months. We randomly selected household and interviewed mothers and /or observed vaccination cards when available to collect data on child's immunization status. We also collected the geographic location of all villages within the ten Kebeles using a Handheld Global Positioning System (GPS) (Garmin GPSMAP®). We analyzed the spatial distribution of under immunization and clustering using the SatScan® software which employs a purely spatial Bernoulli's model. We also ran a logistic regression model to help evaluate the causes of clustering.
We found that only 22.4% [95% CI: 18.9, 26.4%] of children were fully immunized. This study identified one significant cluster of under immunization among children 12-23 months of age within the Butajira HDSS (relative risk (RR) = 1.24,P < 0·01). We found that children residing in this cluster had more than 1.24 times risk of under immunization compared with children residing outside of the identified cluster. We found significant differences with regard to Maternal Tetanus Toxoid immunization status and place of delivery between cases found within a spatial cluster and cases found outside the cluster. For example, the odds of home delivery is more than two times [AOR 2.21: 95%CI; 1.06, 4.63] among children within an identified spatial cluster than the odds among children found outside the identified cluster.
Under immunization of 12-23 months old children and under immunization with specific vaccines such as Polio, BCG, DPT (1-3) and Measles clustered geographically. Spatial studies could be effective in identifying geographic areas of under immunization for targeted intervention like in this study to gear health education to the specific locality.
免疫接种对于全球每年预防200万至300万人死亡至关重要，并且它是最具成本效益的卫生干预措施之一，这一点已得到广泛认可。尽管免疫接种具有诸多优势，但埃塞俄比亚的免疫接种情况仍远未达到联合国可持续发展目标所设定的到2030年所有国家实现全面免疫的目标。2016年埃塞俄比亚人口与健康调查（EDHS）报告称，总体全程免疫接种率仅为38.3%。本研究的目的是评估12至23个月大儿童免疫接种不足的空间分布，并进一步确定布塔吉拉卫生与人口监测点（HDSS）免疫接种不足聚集的决定因素。
2016年3月至4月，我们在布塔吉拉HDSS开展了一项基于社区的横断面调查。我们收集了总共482名12至23个月大儿童的免疫接种状况数据。我们随机选择家庭，并采访母亲和/或在有疫苗接种卡时查看卡片，以收集儿童免疫接种状况的数据。我们还使用手持式全球定位系统（GPS）（佳明GPSMAP®）收集了十个行政区内所有村庄的地理位置。我们使用采用纯空间伯努利模型的SatScan®软件分析免疫接种不足的空间分布和聚集情况。我们还进行了逻辑回归模型分析，以帮助评估聚集的原因。
我们发现只有22.4%[95%置信区间：18.9，26.4%]的儿童实现了全程免疫。本研究在布塔吉拉HDSS内12至23个月大的儿童中确定了一个显著的免疫接种不足聚集区（相对风险（RR）=1.24，P<0.01）。我们发现，居住在该聚集区内的儿童免疫接种不足的风险是居住在已确定聚集区外儿童的1.24倍以上。我们发现，在空间聚集区内发现的病例与聚集区外发现的病例在产妇破伤风类毒素免疫接种状况和分娩地点方面存在显著差异。例如，在已确定的空间聚集区内的儿童中，在家分娩的几率是在已确定聚集区外儿童的两倍多[AOR 2.21：95%置信区间；1.06，4.63]。
12至23个月大儿童的免疫接种不足以及脊髓灰质炎、卡介苗、百白破（1 - 3剂）和麻疹等特定疫苗的免疫接种不足在地理上呈聚集状态。空间研究对于识别免疫接种不足的地理区域以进行有针对性的干预可能是有效的，就像本研究中针对特定地区开展健康教育一样。
