Chen F, Li K R, Li W B, Tian S H, Li P, Zhao Y J, Yang J, Yang H, Luo B R, Ma J H, Hao M M, Chen S R, Liu Y H, Luo T P
Dali Bai Autonomous Prefecture Institute of Schistosomiasis Control, Dali, Yunnan 671000, China.
Heqing County Institute of Schistosomiasis Control, Yunnan Province, China.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi. 2021 Dec 13;34(1):81-84. doi: 10.16250/j.32.1374.2021065.
To compare the effectiveness of loop-mediated isothermal amplification (LAMP) assay and microscopic examinations for detection of infections in in transmission-interrupted regions, so as to provide insights into the optimization of snail surveillance tools in these regions.
Four hilly schistosomiasis-endemic villages where transmission interruption was achieved were selected in Heqing County of Yunnan Province as the study villages, including Xinzhuang and Gule villages in hilly regions and Lianyi and Yitou villages in dam regions. Snail survey was performed by means of systematic sampling combined with environmental sampling in July 2018. All captured snails were identified for infections using microscopy. In addition, 10 to 20 snails were randomly sampled from each snail habitat following microscopy, numbered according to environments and subjected to LAMP assay. The positive rate of settings with -infected snails was compared among villages.
A total of 7 949 living snails were captured from 83 snail habitats in 4 villages, and no infection was detected in snails. There were 226 mixed samples containing 1 786 snails subjected to LAMP assay, and positive LAMP assay was found in 3 mixed samples from 3 snail habitats in 2 dam villages. The positive rates of settings with -infected snails were comparable between Lianyi Village (one setting) and Yitou Village (2 set tings) (5.89% vs. 14.29%, = 0.344). However, the overall positive rate of settings with -infected snails was significantly higher in dam villages (9.67%, 3/31) than in hilly villages (0) ( = 0.048).
LAMP assay is more sensitive to detect infections in than conventional microcopy method, which may serve as a supplementary method for detection of infections in in high-risk snail habitats in hilly transmission-interrupted regions.
比较环介导等温扩增（LAMP）检测法与显微镜检查法在传播阻断地区检测钉螺感染的效果，为优化这些地区的钉螺监测工具提供依据。
选取云南省鹤庆县已实现传播阻断的4个山丘型血吸虫病流行村作为研究村，包括山区的新庄和古乐村以及坝区的联邑和邑头村。2018年7月采用系统抽样结合环境抽样的方法进行钉螺调查。所有捕获的钉螺均通过显微镜检查确定是否感染。此外，在显微镜检查后，从每个钉螺栖息地随机抽取10至20只钉螺，按环境编号并进行LAMP检测。比较各村感染钉螺环境的阳性率。
从4个村的83个钉螺栖息地共捕获7949只活钉螺，未检测到钉螺感染。对226份共1786只钉螺的混合样本进行LAMP检测，在2个坝区村的3个钉螺栖息地的3份混合样本中检测到LAMP阳性。联邑村（1个环境）和邑头村（2个环境）感染钉螺环境的阳性率相当（5.89%对14.29%，P = 0.344）。然而，坝区村感染钉螺环境的总体阳性率（9.67%，3/31）显著高于山区村（0）（P = 0.048）。
LAMP检测法在检测钉螺感染方面比传统显微镜检查法更敏感，可作为山丘型传播阻断地区高风险钉螺栖息地检测钉螺感染的补充方法。
