Institut Sénégalais de Recherches Agricoles/Laboratoire National de l'Elevage et de Recherches Vétérinaires, BP 2057, Dakar-Hann, Senegal.
Laboratoire d'Ecologie Vectorielle et Parasitaire, Département de Biologie Animale, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar, Senegal.
BMC Ecol. 2019 Nov 1;19(1):45. doi: 10.1186/s12898-019-0261-9.
Vector-borne diseases are among the leading causes of morbidity and mortality in humans and animals. In the Afrotropical region, some are transmitted by Culicoides, such as Akabane, bluetongue, epizootic haemorrhagic fever and African horse sickness viruses. Bluetongue virus infection has an enormous impact on ruminant production, due to its high morbidity and mortality rates.
A nationwide Culicoides trapping campaign was organized at the end of the 2012 rainy season in Senegal. A Maximum Entropy approach (MaxEnt), Boosted Regression Tree (BRT) method and Ecological Niche Factor Analysis (ENFA) were used to develop a predictive spatial model for the distribution of Culicoides, using bio-climatic variables, livestock densities and altitude.
The altitude, maximum temperature of the warmest month, precipitation of the warmest quarter, mean temperature of the wettest quarter, temperature seasonality, precipitation of the wettest quarter and livestock density were among the most important factors to predict suitable habitats of Culicoides. Culicoides occurrences were, in most of the cases, positively correlated to precipitation variables and livestock densities; and negatively correlated to the altitude and temperature indices. The Niayes area and the Groundnut basin were the most suitable habitats predicted.
We present ecological niche models for different Culicoides species, namely C. imicola, C. oxystoma, C. enderleini and C. miombo, potential vectors of bluetongue virus, on a nationwide scale in Senegal. Through our modelling approach, we were able to determine the effect of bioclimatic variables on Culicoides habitats and were able to generate maps for the occurrence of Culicoides species. This information will be helpful in developing risk maps for disease outbreaks.
虫媒传染病是人类和动物发病率和死亡率的主要原因之一。在热带非洲地区，有些疾病是由库蠓传播的，如阿卡斑病毒、蓝舌病、马传染性贫血病毒和非洲马瘟病毒。蓝舌病病毒感染对反刍动物的生产造成了巨大影响，因为其发病率和死亡率都很高。
2012 年雨季结束时，塞内加尔组织了一次全国性的库蠓诱捕活动。采用最大熵法（MaxEnt）、增强回归树（BRT）方法和生态位因子分析（ENFA），利用生物气候变量、牲畜密度和海拔，建立了库蠓分布的预测空间模型。
海拔、最热月最高温度、最暖季度降水量、最湿季度平均温度、温度季节性、最湿季度降水量和牲畜密度是预测库蠓适宜栖息地的最重要因素。库蠓的发生与降水变量和牲畜密度呈正相关，与海拔和温度指数呈负相关。尼耶斯地区和花生盆地是预测最适宜的栖息地。
我们在塞内加尔全国范围内提出了不同库蠓物种（即 C. imicola、C. oxystoma、C. enderleini 和 C. miombo）的生态位模型，这些物种是蓝舌病病毒的潜在传播媒介。通过我们的建模方法，我们能够确定生物气候变量对库蠓栖息地的影响，并能够生成库蠓物种发生的地图。这些信息将有助于开发疾病爆发的风险地图。
