The rapid and unplanned urbanization of African cities is considered to increase the risk of urban malaria transmission. The present study objective was to assess factors influencing the spatio-temporal distribution of Anopheles gambiae s.l. larvae in the city of Yaoundé, Cameroon. All water bodies were checked once every 2 months for the presence of mosquito larvae from March 2017 to May 2018 in 32 districts of Yaoundé. Physico-chemical characteristics including the size, depth, turbidity, pH, temperature, conductivity, sulfates, organophosphates, hydrogen peroxide (H2O2), conductivity, iron and calcium were recorded and analyzed according to anopheline larvae presence or absence. High resolution satellite images from landsat sentinel Enhanced Thematic Mapper were used for spatial mapping of both field and environmental variables. Bivariate and multivariate logistic regression models were used to identify variables closely associated with anopheline larvae distribution. A total of 18 696 aquatic habitats were checked and only 2942 sites (15.7%) contained anopheline larvae. A high number of sites with anopheline larvae (≥ 69%) presented late instar larvae (L3, L4 and pupae). Anopheline mosquito larvae were sampled from a variety of breeding sites including puddles (51.6%), tire prints (12.9%), wells (11.7%) and drains (11.3%). Bivariate logistic regression analyses associated anopheline larvae presence with the absence of predators, absence of algae, absence of vegetation and depth of less than 1 m. Conductivity, turbidity, organophosphates, H2O2 and temperature were significantly high in breeding sites with anopheline larvae than in breeding sites without these larvae (P <  0.1). Anopheline species collected included An. coluzzii (91.1%) and An. gambiae s.s. (8.9%). GIS mapping indicated a heterogeneous distribution of anopheline breeding habitats in the city of Yaoundé. Land cover analysis indicated high variability of the city of Yaoundé’s landscape. The data confirms adaptation of An. gambiae s.l. to the urban domain in the city of Yaoundé and calls for urgent actions to improve malaria vector control.

中文翻译：

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喀麦隆雅温得城市环境中冈比亚按蚊幼虫的空间分布

非洲城市的快速和无计划的城市化被认为增加了城市疟疾传播的风险。本研究的目的是评估影响喀麦隆雅温得市冈比亚按蚊幼虫时空分布的因素。从2017年3月到2018年5月，在雅温得32个地区，所有水体每2个月检查一次蚊虫幼虫的存在。记录并根据an鱼幼虫的存在与否，记录并分析其理化特性，包括大小，深度，浊度，pH，温度，电导率，硫酸盐，有机磷酸盐，过氧化氢（H2O2），电导率，铁和钙。来自Landats定点增强型专题制图仪的高分辨率卫星图像用于野外和环境变量的空间制图。使用双变量和多元逻辑回归模型来确定与按蚊幼虫分布密切相关的变量。总共检查了18 696个水生栖息地，只有2942个地点（15.7％）含有按蚊幼虫。大量带有按蚊幼虫的部位（≥69％）呈晚龄幼虫（L3，L4和p）。从各种繁殖地点取样了按蚊蚊幼虫，包括水坑（51.6％），轮胎印迹（12.9％），水井（11.7％）和排水管（11.3％）。双变量逻辑回归分析分析了相关的按蚊幼虫的存在，没有捕食者，没有藻类，没有植被以及深度小于1 m。电导率，浊度，有机磷酸盐，带有按蚊幼虫的繁殖场所的H2O2和温度显着高于没有这些幼虫的繁殖场所（P <0.1）。收集到的按蚊种包括An。coluzzii（91.1％）和An。冈比亚SS（8.9％）。GIS测绘表明雅温得市的按蚊繁殖生境分布不均。土地覆盖分析表明，雅温得市的地貌变化很大。数据证实An的适应。冈比亚一直流向雅温得市的市区，并呼吁采取紧急行动改善对疟疾的控制。土地覆盖分析表明，雅温得市的地貌变化很大。数据证实An的适应。冈比亚一直流向雅温得市的市区，并呼吁采取紧急行动改善对疟疾的控制。土地覆盖分析表明，雅温得市的地貌变化很大。数据证实An的适应。冈比亚一直流向雅温得市的市区，并呼吁采取紧急行动改善对疟疾的控制。