Abstract:

【Abstract】 Objective  To make an accurate knowledge on the risk status of schistosomiasis transmission in endemic areas in Hunan Province in 2014 for evidences to plan scientific strategies for control and prevention of this disease. Methods  Twenty-five administrative villages in 13 counties (cities, districts, farms) were selected as risk surveillance sites, and hatching test(1 aliquot of feces subjected to 3 tests) was used to determine the schistosome infection status in all livestock and feces collected in open fields. Systematic sampling method was used to measure the status of snail prevalence, and modified crushing-cercariae escaping method and loop-mediated isothermal amplification(LAMP) technique were applied to detecting the infected snails. Activities of humans and livestock were also observed in the susceptible zones within the 25 surveillance villages. Results  Livestock were being fed in 92% of surveillance villages. The infection rate was 1.10%, 1.00%, 1.00% and 0.93%, respectively in Qingang village under Quyuan administrative district, Jichang village and Beihu village of Yueyang county, Kangling village of Yuanjiang city. Sails were found in marshlands within the 25 surveillance villages, and no positive snails were seen in 23 samples obtained in even number frames and tested with crushing-cercariae escaping method. However, 6 positive samples(collected in the odd number frames from the marshland in Mingxing, Hanshou county; Zhongxin, Jinshi city; Yuantan and Dongfanghong, Xiangying county; Baota, Quyuan administrative district and Dingshan, Yunxi district) were detected with LAMP method. Livestock were pastured in 56% of risk areas, and the livestock were over 50 in 4 the susceptible areas(the marshland in Baota; Qingang, Quyuan administrative district; Dingshan and Xinshe, Yunxi district). Human actives(totally 43 people being seen) were found in 44% of risk areas. 607 aliquots of livestock feces, including 592 aliquots of feces from cattle and 15 from goats, obtained in the open fields within 96% of the surveillance sites were free of positive samples. Conclusion  The surveillance index for snails，livestock and wild feces may provide scientific evidence for assessment of the risks of schistosomiasis transmission in endemic areas.

Key words: Schistosomiasis, Risk surveillance, Hunan Province