Ibrahim S A, Abdallah A, Saleh E A, Osterhaus A D M E, De Swart R L
Department of Paediatrics, University of Khartoum, Sudan.
Epidemiol Infect. 2006 Feb;134(1):79-85. doi: 10.1017/S0950268805004620.
We conducted a prospective birth cohort study in rural Sudan to assess measles virus (MV)-specific antibody levels at different time points in infancy. Dried blood spots were collected on filter paper at birth (cord blood) and at ages 6, 12 and 24 months (heel-prick). Maternally derived MV-specific antibody levels were high in cord blood samples, but at the age of 6 months had dropped below cut-off values in half of the infants. By extrapolation it was concluded that the current Expanded Programme of Immunization (EPI) target age for measles vaccination of 9 months was an appropriate choice for this area. At the age of 24 months acquired MV-specific antibodies were detected in 65-85% of the cohort, which corresponded well with the 79% of infants reported to be vaccinated by this age. This study demonstrates the usefulness of filter paper blood samples for seroepidemiological studies in developing countries.
我们在苏丹农村地区开展了一项前瞻性出生队列研究，以评估婴儿期不同时间点的麻疹病毒（MV）特异性抗体水平。在出生时（脐带血）以及6、12和24月龄（足跟采血）时采集滤纸干血斑。脐带血样本中母体来源的MV特异性抗体水平较高，但在6月龄时，半数婴儿的抗体水平已降至临界值以下。通过推断得出结论，当前扩大免疫规划（EPI）规定的9月龄麻疹疫苗接种目标年龄对于该地区是一个合适的选择。在24月龄时，该队列中65%-85%的婴儿检测到获得性MV特异性抗体，这与报告的该年龄组79%的婴儿已接种疫苗的情况非常吻合。这项研究证明了滤纸血样在发展中国家血清流行病学研究中的实用性。
