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.
ABSTRACT
Objective To understand the characteristics of schistosome cercarial infested water contact of residents in Poyang Lake endemic areas after the operation of Three Gorges Project,so as to provide the evidence for formulating a well-directed con-trol strategy. Methods The residents in two villages in schistosomiasis endemic areas were selected and surveyed for their activi-ties of infested water contacts by questionnaire. Results The proportion and frequency of infested water contacts of residents in Poyang Lake region were high and the average rate of infested water contacts was 69.77%,and 98.96%of infested water contacts occurred in spring,summer and autumn. The main ways of infested water contacts were fishing/swimming/playing for adult men, washing clothes/fishing for adult women,and swimming/playing for school children,respectively. The rates of infested water con-tacts were 73.33%,71.63%and 61.87%in adult men,women and school children,respectively. The frequencies of infested water contacts>1 time/week,1 time/week-1 time/month,and<1 time/month were 62.61%,23.74%and 13.66%respectively. Conclu-sions The infested water contacts mainly occurs in spring,summer and autumn,and the main way of infested water contacts was fishing. Farming and mowing grass,which had been the primary way,now become the secondary way for the adult residents.