Anekwe Tobenna D, Newell Marie-Louise, Tanser Frank, Pillay Deenan, Bärnighausen Till
USDA Economic Research Service, Washington, DC 20224, USA; Wellcome Trust Africa Centre for Health and Population Studies, Mtubatuba 3935, South Africa.
Wellcome Trust Africa Centre for Health and Population Studies, Mtubatuba 3935, South Africa; University of Southampton, Southampton SO17 1BJ, UK.
Vaccine. 2015 Sep 11;33(38):5020-6. doi: 10.1016/j.vaccine.2015.04.072. Epub 2015 Apr 30.
Because measles vaccination prevents acute measles disease and morbidities secondary to measles, such as undernutrition, blindness, and brain damage, the vaccination may also lead to higher educational attainment. However, there has been little evidence to support this hypothesis at the population level. In this study, we estimate the causal effect of childhood measles vaccination on educational attainment among children born between 1995 and 2000 in South Africa.
We use longitudinal data on measles vaccination status and school grade attainment among 4783 children. The data were collected by the Wellcome Trust Africa Centre Demographic Information System (ACDIS), which is one of Africa's largest health and demographic surveillance systems. ACDIS is located in a poor, predominantly rural, Zulu-speaking community in KwaZulu-Natal, South Africa. Using mother fixed-effects regression, we compare the school grade attainment of siblings who are discordant in their measles vaccination status but share the same mother and household. This fixed-effects approach controls for confounding due to both observed and unobserved factors that do not vary between siblings, including sibling-invariant mother and household characteristics such as attitudes toward risk, conscientiousness, and aspirations for children. We further control for a range of potential confounders that vary between siblings, such as sex of the child, year of birth, mother's age at child's birth, and birth order. We find that measles vaccination on average increases school grade attainment by 0.188 grades (95% confidence interval, 0.0424-0.334; p=0.011).
Measles vaccination increased educational attainment in this poor, largely rural community in South Africa. For every five to seven children vaccinated against measles, one additional school grade was gained. The presence of a measles vaccination effect in this community is plausible because (i) measles vaccination prevents measles complications including blindness, brain damage, and undernutrition; (ii) a large number of number of children were at risk of contracting measles because of the comparatively low measles vaccination coverage; and (iii) significant measles transmission occurred in the community where this study took place during the study observation period. Our results demonstrate for the first time that measles vaccination affects human development not only through its health effects but also through its effects on education.
由于麻疹疫苗接种可预防急性麻疹疾病以及麻疹继发的诸如营养不良、失明和脑损伤等病症，该疫苗接种还可能带来更高的教育成就。然而，在人群层面几乎没有证据支持这一假设。在本研究中，我们估计了南非1995年至2000年出生儿童的儿童期麻疹疫苗接种对教育成就的因果效应。
我们使用了4783名儿童的麻疹疫苗接种状况和学业成绩的纵向数据。这些数据由惠康信托非洲中心人口信息系统（ACDIS）收集，该系统是非洲最大的健康和人口监测系统之一。ACDIS位于南非夸祖鲁 - 纳塔尔省一个贫穷、主要为农村且讲祖鲁语的社区。使用母亲固定效应回归，我们比较了麻疹疫苗接种状况不一致但有相同母亲和家庭的兄弟姐妹的学业成绩。这种固定效应方法控制了由于兄弟姐妹之间不变的观察到和未观察到的因素导致的混杂，包括兄弟姐妹不变的母亲和家庭特征，如对风险的态度、尽责性以及对孩子的期望。我们进一步控制了一系列兄弟姐妹之间变化的潜在混杂因素，如孩子的性别、出生年份、母亲生育孩子时的年龄以及出生顺序。我们发现麻疹疫苗接种平均使学业成绩提高0.188个年级（95%置信区间，0.0424 - 0.334；p = 0.011）。
在南非这个贫穷的、主要为农村的社区，麻疹疫苗接种提高了教育成就。每五到七个接种麻疹疫苗的儿童中，就多获得一个年级的学业进步。该社区存在麻疹疫苗接种效应是合理的，因为（i）麻疹疫苗接种可预防包括失明、脑损伤和营养不良在内的麻疹并发症；（ii）由于麻疹疫苗接种覆盖率相对较低，大量儿童有感染麻疹的风险；（iii）在本研究的观察期内，本研究所在社区发生了显著的麻疹传播。我们的结果首次证明麻疹疫苗接种不仅通过其对健康的影响，还通过其对教育的影响来影响人类发展。
