Assaré Rufin K, Lai Ying-Si, Yapi Ahoua, Tian-Bi Yves-Nathan T, Ouattara Mamadou, Yao Patrick K, Knopp Stefanie, Vounatsou Penelope, Utzinger Jürg, N'Goran Eliézer K
Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Basel; University of Basel, Basel, Switzerland; Unité de Formation et de Recherche Biosciences, Université Félix Houphouët-Boigny, Abidjan; Centre Suisse de Recherches Scientifiques en Côte d'Ivoire, Abidjan.
Geospat Health. 2015 Jun 3;10(1):345. doi: 10.4081/gh.2015.345.
Schistosomiasis poses a considerable public health burden in sub- Saharan Africa and a sound understanding of the spatial distribution facilitates to better target control interventions. The objectives of this study were i) to assess the prevalence of Schistosoma mansoni among school-aged children in four regions of western Côte d'Ivoire; ii) to determine demographic, climatic and environmental factors that influence the distribution of S. mansoni; and iii) to map and predict the distribution of S. mansoni in non-sampled locations. Parasitological surveys were carried out in 264 schools from June to December 2011. In each school, we aimed to examine 50 children for S. mansoni infection using duplicate Kato-Katz thick smears. Schools were georeferenced using a hand-held global positioning system receiver. Demographic data were obtained from readily available school lists, while climatic and environmental data were extracted from open-access remote sensing databases. Multivariable, binary non-spatial models and a Bayesian geostatistical logistic regression model were used to identify demographic, climatic and environmental risk factors for S. mansoni infection. Risk maps were developed based on observed S. mansoni prevalences and using Bayesian geostatistical models to predict prevalences at non-sampled locations. Overall, 12,462 children provided a sufficiently large stool sample to perform at least one Kato-Katz thick smear. The observed overall prevalence of S. mansoni infection was 39.9%, ranging from 0 to 100% at the unit of the school. Bayesian geostatistical analysis revealed that age, sex, altitude and difference between land surface temperature at day and night were significantly associated with S. mansoni infection. The S. mansoni risk map presented here is being been used by the national schistosomiasis control programme for spatial targeting of praziquantel and other interventions.
血吸虫病在撒哈拉以南非洲构成了相当大的公共卫生负担，深入了解其空间分布有助于更好地确定控制干预措施的目标。本研究的目的是：（i）评估科特迪瓦西部四个地区学龄儿童曼氏血吸虫的流行情况；（ii）确定影响曼氏血吸虫分布的人口、气候和环境因素；（iii）绘制并预测未抽样地区曼氏血吸虫的分布。2011年6月至12月在264所学校开展了寄生虫学调查。在每所学校，我们旨在使用两份Kato-Katz厚涂片检查50名儿童是否感染曼氏血吸虫。使用手持式全球定位系统接收器对学校进行地理定位。人口数据从现有的学校名单中获取，而气候和环境数据则从开放获取的遥感数据库中提取。使用多变量二元非空间模型和贝叶斯地理统计逻辑回归模型来确定曼氏血吸虫感染的人口、气候和环境风险因素。根据观察到的曼氏血吸虫流行率绘制风险图，并使用贝叶斯地理统计模型预测未抽样地区的流行率。总体而言，12462名儿童提供了足够大的粪便样本以进行至少一次Kato-Katz厚涂片检查。观察到的曼氏血吸虫感染总体流行率为39.9%，在学校层面从0%到100%不等。贝叶斯地理统计分析表明，年龄、性别、海拔以及昼夜地表温度差异与曼氏血吸虫感染显著相关。此处呈现的曼氏血吸虫风险图正被国家血吸虫病控制规划用于吡喹酮和其他干预措施的空间定位。
