title: [Study on potential risks of schistosomiasis transmission in Grand Canal West water diversion route of eastern route project of South-to-North Water Diversion Project].
abstract: OBJECTIVE
  To understand the potential risks of Oncomelania hupensis diffusion and schistosomiasis transmission in the Grand Canal west water diversion route of the eastern route project of the South-to-North Water Diversion Project.
  
  
  METHODS
  The engineering layout from Nanyun west floodgate to Hongze Lake, the aquaculture along Hongze Lake, and the data of hydrology and transferred water were investigated. The investigations on Oncomelania hupensis and schistosomiasis were carried out in the surveillance sites of Jinbao Channel and Hongze Lake. The possibilities of snail spreading and schistosomiasis transmission were researched.
  
  
  RESULTS
  Oncomelania snails lacked their breeding environment and ecological condition in the Hongze Lake region. The engineering facilities of the Jinhu and Hongze pumping stations went against the snail spreading. The water levels at all steps decreased gradually from Hongze Lake to Jinbao Channel. Therefore, the pumping stations were necessary when the water transferred to Hongze Lake. The multi-year average diverted water volume reached 2.558 billion cubic meters a year in the Jinbao Channel. Of the total diverted water volume, there was 75% of the volume in drought years. The Oncomelania snails were not found in the surveillance sites of the Jinbao Channel and the Hongze Lake region from 2008 to 2011. A total of 3 088 residents were examined with the serology tests and the positive rate was 0.29% in 2008. Totally 4 758 overwater flow people were examined with the serology tests and the positive rate was 2.42% from 2008 to 2011. The serum positive rate was higher in the overwater flow people than that in the residents (chi2 = 0.083, P < 0.01). The stool examinations were all negative in the above mentioned serum positive people.
  
  
  CONCLUSIONS
  The Hongze Lake area has still no Oncomelania snail breeding and schistosomiasis endemic so far. There are also no schistosomiasis re-prevalent signs in the Jinbao Channel area where schistosomiasis was once prevalent. The Oncomelania snail breeding and diffusion, and schistosomiasis endemic are unlikely to appear in the Grand Canal west water diversion route of the eastern route project of the South-to-North Water Diversion and Hongze Lake area.
authors.affiliation: Jiangsu Institute of Schistosomiasis, Wuxi 214064, China.
authors.forename: Yi-Xin
authors.initials: YX
authors.lastname: Huang
authors.forename: Tian-Chun
authors.initials: TC
authors.lastname: Li
authors.forename: De-Rong
authors.initials: DR
authors.lastname: Hang
authors.forename: Dao-Kuan
authors.initials: DK
authors.lastname: Sun
authors.forename: Bo
authors.initials: B
authors.lastname: Zheng
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Zhang
authors.forename: Shou-Guo
authors.initials: SG
authors.lastname: Yuan
authors.forename: Si-Hong
authors.initials: SH
authors.lastname: Chen
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Wen-Zhou
authors.initials: WZ
authors.lastname: Yang
mesh_terms: D000818:Animals; D002681:China; D003140:Communicable Disease Control / Q000379:methods*; D006801:Humans; D012307:Risk Factors; D045483:Rivers / Q000469:parasitology*; D012552:Schistosomiasis / Q000469:parasitology / Q000517:prevention & control / Q000635:transmission*; D012908:Snails / Q000254:growth & development / Q000469:parasitology*