ABSTRACT
Objective To study epidemic of schistosomiasis in the Qiandao Lake reservoir area,and to provide a reference for prevention and control of schistosomiasis in the construction of large water conservancy projects in the epidemic area of schistosomiasis.Methods The data over the years of snail condition and monitoring of schistosomiasis before and after building the dam,and water conservancy project reconstruction related information were collected.Based on the survey results of the river channel,the lake beach and the dissipation zone in the reservoir area,the influence of Xin'an River water conservancy project on epidemic of schistosomiasis in the Qiandao Lake reservoir area was analyzed,and the epidemic factors of the schistosomiasis in the Three Gorges reservoir were compared and analyzed.Results Before the dam was built,an area of 38 144 000 m2 was examined but Oncomelania was undetected.The Qiandao Lake reservoir area belonged to a non epidemic area of schistosomiasis.After the dam was built,557 cases of schistosomiasis were found in 6 232 immigrants during 1962-1965,resulting in an imported epidemic.In 1970-1980,an area of 379 654 m2 in which Oncomelania was found was examined and snails were mainly distributed in some rice fields and ditches in the end of the reservoir.949 cases of local schistosomiasis were found in the snails.The condition and condition of the snail are gradually controlled through several decades of comprehensive prevention and control.Compared with the epidemic factors of schistosomiasis in Qiandao Lake and the Three Gorges reservoir,the environment of elevation beach and ecologically fragile fluctuation zone coexist in the two reservoir areas.Conclusion From the long-term longitudinal monitoring data of the Qiandao Lake reservoir area and the epidemic regularity of schistosomiasis and the comparison with the ecology of the Three Gorges reservoir,it is concluded that the two reservoir areas will not cause a large range of schistosomiasis epidemic in general,but it does not exclude the possibility of the breeding of the inputting Oncomelania.