Growth and decline of Oncomelania hupensis status in Duchang County at North shore of Poyang Lake,2005-2012 / 中国血吸虫病防治杂志

ABSTRACT

Objective To understand the dynamic of Oncomelania hupensis snail status in Duchang County at north shore of Poyang Lake so as to provide the evidence for formulating the strategy of schistosomiasis control. Methods The data about the snail status in Duchang County from 2005 to 2012 were collected and the change trend of the snail status was analyzed. Re?sults From 2005 to 2012 all the average density of living snails the occurrence rate of frames with living snails the density of infected snails and the area with infected snails showed a trend of sharp decline and stayed at a low level. Compared to 2005 the above 4 indexes in 2008 decreased by 70.06% 90.33% 79.48% and 37.88% respectively and those in 2012 decreased by 99.35% 98.98% 99.33% and 93.84% respectively. The infection rates of snails fluctuated between 0.06%and 0.53%which showed a trend of first decrease and then increase. The snail area maintained at the level of 2 052.5 hm2 since 2007. Con?clusions Most of the indexes of the snail status in Duchang County have decreased to the lowest level in history since 2012 but the snail area is stable and the infection rate of snails shows a fluctuation trend which suggests that the risks of schistosomia?sis transmission still exist and the snail control still should be strengthened.