Distribution pattern of the snail intermediate host of schistosomiasis japonica in the Poyang Lake region of China
Distribution pattern of the snail intermediate host of schistosomiasis japonica in the Poyang Lake region of China
复制标题
我国鄱阳湖地区日本血吸虫病钉螺中间宿主的分布格局.
DOI：
10.1186/s40249-019-0534-8
复制
发表时间：
2019-03-29
影响因子：
8.1
通讯作者：
Lin, Dan-Dan
中科院分区：
文献类型：
--
作者：
Hu, Fei;Ge, Jun;Lin, Dan-Dan
随着2003年三峡大坝的关闭，鄱阳湖的水文发生了巨大的变化，导致鄱阳湖环境发生了重大变化。为了评估对血吸虫病的影响，本研究对鄱阳湖支流钉螺中间寄主湖北钉螺的时空分布格局进行了评估。该研究结果对未来的蜗牛控制策略具有重要意义，从而消除疾病。方法采用ArcGIS软件将鄱阳湖周边湿地随机划分为200 × 200 m的矢量网格，随机选取调查网格。采用50 × 50 m的调查框，以每个网格的一条边线为起跑线，在选定的每个网格内进行蜗牛调查。在每个调查网格中使用不少于10帧的全球定位系统（GPS）记录。采集每帧所有钉螺，镜检检测感染情况。所有帧的高度数据都是从湖底地形图中提取的，以便分析平均高度。收集所有钉螺调查资料，采用SPSS 20.0软件进行统计分析，确定鄱阳湖不同地区钉螺镜框活螺百分率和平均活螺密度的差异。随后确定了蜗牛出没的沼泽地和蜗牛巢穴的海拔高度。结果共调查了1159个潜在钉螺采样网格，其中15 231帧（0.1 m2/帧）被调查。1241帧有活的oncomelanasnails，占总帧数的8.15%。平均活螺密度为0.463/0.1 m2，每帧最多57只。鄱阳湖南段有螺框的比例（8.13%）与北段无统计学差异（8.21%）。北段活螺平均密度（0.164/0.1 m2）显著高于南段（0.141/0.1 m2） （F= 6.727， P= 0.010）。在湖的南部，蜗牛居住的沼泽地海拔高度在11 ~ 16 m之间，在海拔12 ~ 13 m和15 ~ 16 m可进一步细分为两个蜗牛集中带。湖北海拔9 ~ 16 m为蜗牛栖息湿地，海拔12 ~ 14 m为蜗牛密集区。结论鄱阳湖地区蜗牛出没的湿地海拔高度在9 ~ 16 m之间。由于大坝关闭后水位的变化，蜗牛的分布和栖息地已经向湖的北部和较低的海拔移动。根据目前蜗牛栖息地的地质特征，集中灭螺应发生在蜗牛密集、牛和人交通频繁的北部地区。以这些确定的传播“热点”为目标将有助于消除努力。
BackgroundWith the closure of the Three Gorges Dam in 2003 the hydrology of Poyang Lake was altered dramatically leading to significant changes in the environment. In order to assess the impact on schistosomiasis this study assessed the spatial and temporal patterns of the snail intermediate host,Oncomelania hupensisin the Poyang Lake tributaries. The results of the study have important implications for future snail control strategies leading to disease elimination.MethodsThe marshland area surrounding Poyang Lake was divided randomly into 200 × 200 m vector grids using ArcGIS software, and the surveyed grids were randomly selected by the software. The snail survey was conducted in each selected grid using a survey frame of 50 × 50 m with one sideline of each grid serving as the starting line. No less than ten frames were used in each surveyed grid with Global Positioning System (GPS) recordings for each. All snails in each frame were collected to determine infection status by microscopy. Altitude data for all frames were extracted from a lake bottom topographic map in order to analyze the average altitude. All snail survey data were collected and statistically analyzed with SPSS 20.0 software in order to determine the difference of the percentage of frames with living snails and mean density of living snails in different regions of Poyang Lake. The altitude of the snail-infested marshlands and snail dens were subsequently identified.ResultsA total of 1159 potential snail sampling grids were surveyed, of which 15 231 frames (0.1 m2/frame) were investigated. 1241 frames had liveOncomelaniasnails corresponding to 8.15% of the total number of frames. The mean density of living snails was 0.463/0.1 m2with a maximum of 57 snails per frame. The percent of frames with snails in the southern sector (8.13%) of Poyang Lake did not differ statistically from the north (8.21%). However, the mean density of live snails in the northern sector (0.164/0.1 m2) of the lake was statistically higher (F= 6.727;P= 0.010) than the south (0.141/0.1 m2). In the south of the lake, the elevation of snail-inhabited marshland ranged between 11-16 m, and could be further subdivided into two snail-concentrated belts at 12-13 m of elevation and 15-16 m of elevation respectively. In the north of the lake, the elevation of snail-inhabited marshland ranged between 9-16 m with the elevation of 12-14 m being the snail-concentrated zone.ConclusionsThe elevation of snail-infested marshlands in the Poyang Lake region ranged from 9 to 16 m. The snail distribution and habitat has moved north of the lake and to a lower altitude due to changes in the water level post dam closure. Based on the current geological features of the snail habitant focused mollusciciding should occur in snail dense northern regions with frequent bovine and human traffic. Targeting these identified 'hotspots’ of transmission will assist in elimination efforts.