Maleghemi Sylvester, Anyuon Atem Nathan, Zingbondo Isaac Michael, Legge George Awzenio, Ferede Melisachew Adane, Eweh Patrick Freeman, Mokaya Evans, Musanhu Patience, Karamagi Humphrey, Wanyoike Sarah, Blanc Diana Chang, Olu Olushayo Oluseun, Tegegne Ayesheshem Ademe
Vaccine-Preventable Diseases Programme World Health Organization Country Office, Juba, South Sudan.
Expanded Programme on Immunization Ministry of Health, Juba, Republic of South Sudan.
Open Forum Infect Dis. 2025 Apr 9;12(5):ofaf221. doi: 10.1093/ofid/ofaf221. eCollection 2025 May.
Since establishing routine immunization services in what was then known as Sudan in 1974, South Sudan has not yet introduced the rubella-containing vaccine into its national immunization schedule. This study aims to assess the burden of rubella infection within the existing measles case-based surveillance framework to provide evidence supporting advocacy for introducing the rubella-containing vaccine into the national immunization program.
This study conducted a retrospective descriptive analysis of rubella infection using measles case-based surveillance data from 2013 to 2023. Data were analyzed with descriptive statistics and logistic regression using Epi Info, version 7.
During the study period, 17,987 suspected measles cases were reported, with 4944 serum samples collected. Of these, 2083 (42.1%) were positive for measles immunoglobulin M antibodies. Among 2861 samples that tested negative or indeterminate for measles, 678 (23.7%) tested positive for rubella immunoglobulin M antibodies. The study observed a significant increase in rubella positivity rates from 1.6% in 2014 to 34.4% in 2020. Logistic regression analysis showed that rubella infection was significantly more likely among children aged 5-9 years (odds ratio [OR] = 2.234; 95% confidence interval [CI]; 1.468-3.473, < .001), 10-14 years (OR = 2.101; 95% CI, 1.570-4.428; < .001), and 1-4 years (OR = 1.733; 95% CI, 1.149-2.687; = .003), compared to children aged younger than 1 year (reference group). Rubella positivity was also slightly higher in urban settings than rural areas (OR = 1.139; 95% CI, 1.004-1.527; = .034). Rubella cases demonstrated clear seasonality, with increased cases occurring from December and peaking in March.
The study identified a high prevalence of rubella among young children, particularly those aged 1-9 years and in urban areas, highlighting the need for targeted vaccination strategies. These findings strongly support introducing the rubella vaccine into the national immunization program.
自1974年在当时的苏丹建立常规免疫服务以来，南苏丹尚未将含风疹疫苗纳入其国家免疫规划。本研究旨在评估在现有的基于麻疹病例的监测框架内风疹感染的负担，为支持将含风疹疫苗引入国家免疫计划的宣传提供证据。
本研究利用2013年至2023年基于麻疹病例的监测数据对风疹感染进行回顾性描述性分析。使用Epi Info 7版进行描述性统计和逻辑回归分析数据。
在研究期间，报告了17987例疑似麻疹病例，采集了4944份血清样本。其中，2083例（42.1%）麻疹免疫球蛋白M抗体呈阳性。在2861份麻疹检测呈阴性或不确定的样本中，678例（23.7%）风疹免疫球蛋白M抗体呈阳性。研究观察到风疹阳性率从2014年的1.6%显著增加到2020年的34.4%。逻辑回归分析显示，5至9岁儿童（比值比[OR]=2.234；95%置信区间[CI]；1.468 - 3.473，P<0.001）、10至14岁儿童（OR = 2.101；95% CI，1.570 - 4.428；P<0.001）和1至4岁儿童（OR = 1.733；95% CI，1.149 - 2.687；P = 0.003）感染风疹的可能性显著高于1岁以下儿童（参照组）。城市地区的风疹阳性率也略高于农村地区（OR = 1.139；95% CI，1.004 - 1.527；P = 0.034）。风疹病例呈现明显的季节性，12月起病例增加，3月达到高峰。
该研究确定幼儿中风疹感染率很高，特别是1至9岁儿童和城市地区儿童，突出了针对性疫苗接种策略的必要性。这些发现有力支持将风疹疫苗引入国家免疫计划。
