Study on distribution status of Oncomelania hupensis-intermediate host of Schistosoma japonicum in Jiangxi Province I Analysis of distribution of O. hupen-sis in Poyang Lake area / 中国血吸虫病防治杂志

ABSTRACT

Objective To grasp the distribution status of Oncomelania hupensis snails in Poyang Lake area,so as to provide the evidence for formulating and adjusting the schistosomiasis prevention and control strategy in lake areas. Methods The vec-tor grid was created and sampled randomly by 200 m × 200 m in the spatial database of grassland,and the distribution of snails was investigated in the selected grid by using the method of mechanical sampling by 50 m × 50 m. At the same time,the eleva-tion of investigation points was extracted based on the topographic map of Poyang Lake. Results Totally 949 and 210 investiga-tion points were collected from the south and north of Poyang Lake areas,accounting for 3.04%and 3.21%of all the investiga-tion points in the respective region. The number of investigation points,the appearance rate of snail frame,and the average den-sity of alive snails were 15231,8.15%,and 0.463/0.1 m2,respectively. The elevation of snail distribution area of the south and north Poyang Lake areas were 11-16 m and 9-16 m respectively. The elevation of concentrated snail belts of the south Poyang Lake area were 12-13 m and 15-16 m,and the elevation of concentrated snail belts of the north Poyang Lake area was 12-14 m. Conclusions The distribution of snails is in the range of 9-16 m. The suitable habitats of snail breeding are moving from the south Poyang Lake area to the north Poyang Lake area,and from high elevation to low elevation. In the future,the schistosomia-sis prevention and control measures could be formulated based on the geographical characteristics of current snail distribution in order to consolidate the achievements of schistosomiasis control.