Objective: To investigate the spatial distribution of Oncomelania hupensis snail habitats at the administrative village scale in schistosomiasis-endemic areas of Hubei Province, so as to provide scientific bases for precise control of O. hupensis snails in the province.
Methods: Data regarding snail distribution at the village level in Hubei Province in 2017 were collected to create a spatial analysis database of snail distribution in Hubei Province. The spatial aggregations of O. hupensis distribution were analyzed using Moran's I index and Local Moran's I index. In addition, the distances from schistosomiasis-endemic villages to the Yangtze River were captured using the software ArcGIS 13.0, and their correlations with area of snail habitats were examined with the Spearman correlation method.
Results: O. hupensis snails were mainly distributed in 5 450 endemic villages from 63 counties of 13 cities in Hubei Province in 2017. The global spatial autocorrelation analysis showed spatial aggregations in the areas of historically accumulated snail habitats, current areas of snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment (all Z Scores > 0, all P values < 0.05), and no spatial aggregation was seen in the areas of snail habitats in hilly areas (Z Score > 0, P > 0.05). There were four types of spatial distribution of historically accumulated areas of snail habitats, areas of current snail habitats, areas of snail habitats outside the embankment and snail habitats inside the embankment, including the high-high type (H-H type), high-low type (H-L type), low-high type (L-H type) and random distribution type, and a high percentage of the H-H type was found. There were 340, 125 and 110 endemic villages with the H-H type of areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment, and these villages were mainly concentrated in Wuhan and Jingzhou cities, with almost consistent spatial aggregation locations. There were 319 endemic villages with the H-H type of distribution of snail habitats inside the embankment, which were mainly distributed in Jingzhou, Xiaogan and Huangshi cities. In addition, the areas of historically accumulated snail habitats, current areas of snail habitats and areas of snail habitats outside the embankment negatively correlated with the distance from the endemic villages to the Yangtze River (r = -0.094, P < 0.01; r = -0.225, P < 0.01; r = -0.177, P < 0.01).
Conclusions: The clustering areas of snail habitats along the Yangtze River Basin, notably the villages near the Yangtze River are key regions for snail monitoring and control in Hubei Province.
[摘要] 目的 在行政村尺度上探讨湖北省血吸虫病流行区钉螺空间分布特征, 为精准控制钉螺提供科学依据。方 法 以行政村为单位收集2017年湖北省螺情资料, 构建湖北省钉螺分布空间数据库, 分析钉螺分布的空间聚集性。在 ArcGIS软件支持下, 获得流行村与长江的距离, 分析该距离与有螺面积间的关系。结果 2017年, 湖北省钉螺主要分布 在13个市、63个流行县 (市、区)、5 450个流行村。全局空间自相关分析结果显示, 村级历史累计有螺面积、现有钉螺面 积、垸外和垸内有螺面积存在空间聚集现象 (Z 值均> 0, P 均< 0.05); 山丘型有螺面积呈随机分布, 没有聚集现象 (Z 值> 0, P > 0.05)。聚集和异常值分析结果显示, 历史累计有螺面积、现有钉螺面积、垸外和垸内有螺面积分布模式均有H-H、H-L、L-H和随机分布4种类型, 其中比例较高的是H-H型; 历史累计有螺面积、现有钉螺面积和垸外有螺面积呈H-H聚 集模式的流行村分别有340、125个和110个, 主要聚集在武汉市和荆州市, 且主要聚集空间位置基本一致。垸内有螺面 积呈H-H聚集模式的流行村有319个, 主要分布在荆州市、孝感市和黄石市。历史累计有螺面积、现有钉螺面积和垸外 有螺面积与流行村距长江的距离均呈负相关 (r = −0.094、−0.225和−0.177, P 均< 0.01)。结论 长江流域钉螺孳生的聚 集区, 尤其是距长江较近的流行村是湖北省钉螺监测和防控的重点区域。.
Keywords: Geographic information system; Hubei Province; Oncomelania hupensis; Schistosomiasis; Spatial autocorrelation; Water system.