Kombich Janeth J, Muchai Paul C, Tukei Peter, Borus Peter K
Centre for Virus Research, Kenya Medical Research Institute, Nairobi, Kenya.
BMC Public Health. 2009 Jul 29;9:269. doi: 10.1186/1471-2458-9-269.
Rubella is an infectious and generally mild childhood viral disease. The disease is of public health importance because infection acquired during early pregnancy often results in foetal abnormalities that are classified as congenital rubella syndrome (CRS). The burden of rubella infection in most developing countries in not well documented because of limited epidemiological data. However, availability of an effective vaccine has made it necessary to have all the countries with no routine vaccination schedule to evaluate the burden of disease in order to make informed decisions on rubella vaccination and strategy. To address this gap we conducted a study to determine age-specific rubella seroprevalence rates and related risk factors among primary and pre-primary school children in Uasin Gishu district, Moi's Bridge location of Kenya.
Subjects of the study were 498 pupils from seven primary schools aged 4-20 years. Questionnaire surveys with blood sampling were conducted between January to July 2005. Samples were tested for rubella specific IgG antibody using ELISA test kit (Enzygnost Behring, Germany).
Overall, rubella seropositivity rate was 80% and it increased with age from 59% (among ages 4-6 years) to 94% (ages 14-20 years). Multivariate logistic regression analysis model, showed that age of child and ownership of a television set which is a proxy measure of socio-economic status of family were significantly associated with rubella seropositivity. The odds of rubella seropositivity in a child older than 13 years was more than that in children younger than 7 years (OR = 3.8 95% CI 2.56-5.78). The odds of rubella seropositivity in a child whose family did not own a television set was 3 times higher than that of child whose family owned a set (OR 3.06, 95% CI 1.17-7.97).
The study provides important and highly useful information on rubella age specific seroprevalence rates in Kenya. Advancing age was found to be associated with increased risk of rubella. Low socio-economic factors suggest an increased risk of infection in certain categories of society, and control measures need to target this. Overall, the findings can also be used by policy makers to model introduction of routine rubella vaccination in the country and also other developing countries facing similar challenges. More than half of the children got infected in pre-primary and efforts to control rubella should target pre-school children. These data provides pre-vaccination information that can be used to guide immunization strategy as well as to determine success of an immunization programme.
风疹是一种具有传染性且通常症状较轻的儿童病毒性疾病。该疾病具有公共卫生重要性，因为孕期早期感染风疹往往会导致胎儿出现异常，即先天性风疹综合征（CRS）。由于流行病学数据有限，大多数发展中国风疹感染的负担尚无充分记录。然而，有效疫苗的出现使得所有未实施常规疫苗接种计划的国家有必要评估疾病负担，以便就风疹疫苗接种和策略做出明智决策。为填补这一空白，我们开展了一项研究，以确定肯尼亚莫伊桥地区乌阿辛吉舒县小学和学前儿童中特定年龄的风疹血清阳性率及相关风险因素。
研究对象为来自7所小学的498名4至20岁的学生。2005年1月至7月期间进行了问卷调查并采集血样。使用酶联免疫吸附测定试剂盒（德国贝林公司的Enzygnost）检测样本中的风疹特异性IgG抗体。
总体而言，风疹血清阳性率为80%，且随年龄增长而升高，从4至6岁年龄段的59%增至14至20岁年龄段的94%。多因素逻辑回归分析模型显示，儿童年龄以及作为家庭社会经济地位替代指标的电视机拥有情况与风疹血清阳性显著相关。13岁以上儿童风疹血清阳性的几率高于7岁以下儿童（比值比=3.8，95%置信区间2.56 - 5.78）。家庭没有电视机的儿童风疹血清阳性的几率是家庭拥有电视机儿童的3倍（比值比3.06，95%置信区间1.17 - 7.97）。
该研究提供了关于肯尼亚风疹特定年龄血清阳性率的重要且非常有用的信息。研究发现年龄增长与风疹风险增加相关。社会经济因素较低表明某些社会群体感染风险增加，控制措施需针对这一点。总体而言，研究结果还可供政策制定者用于模拟该国以及面临类似挑战的其他发展中国家引入常规风疹疫苗接种的情况。超过一半的儿童在学前阶段受到感染，控制风疹的努力应针对学龄前儿童。这些数据提供了疫苗接种前信息，可用于指导免疫策略以及确定免疫计划的成效。
