title: [Analysis of trend of Oncomelania snail status in Yangtze River valley of Anhui Province, 1998-2009].
abstract: OBJECTIVE
  To understand the trend of Oncomelania hupensis snail distribution in Yangtze River valley of Anhui Province so as to provide an evidence for making out schistosomiasis prevention and control strategies in the future.
  
  
  METHODS
  The snail data from 1998 to 2009 of the Yangtze River valley in Anhui Province were collected including the snail area, newly occurred and re-occurred snail areas, densities of snails and infected snails, etc., and the trend and influence factors were analyzed.
  
  
  RESULTS
  With several fluctuations, the snail area showed a trend of declining in general after the devastating summer flooding in 1998. From 1998 to 2009, 3 peaks of newly occurred snail areas appeared in 1998, 2004 and 2006 and 2 peaks of reoccurred snail areas appeared in 1998 and 2004. The densities of living snails and infected snails were more severe in banks of the Yangtze River than in islets of the Yangtze River. During 12 years, 1 peak of living snail density appeared in 2003, and 3 peaks of infected snail density appeared in 1999, 2003-2004 and 2006 in the islets of the Yangtze River. The densities of living snails and infected snails in banks of the Yangtze both appeared 1 peak in 1998.
  
  
  CONCLUSIONS
  The distribution of snails in the Yangtze River valley is related to nature, society and financial circumstances, and it is hard to completely perform the snail control in a short-term. Therefore, at the same time of strengthening snail control, we should also strengthen infectious source control.
authors.affiliation: Anhui Institute of Schistosomiasis Control, Hefei 230061, China; 2 Changjiang River Scientific Research Institute, Wuhan, China.
authors.forename: Jia-Chang
authors.initials: JC
authors.lastname: He
authors.forename: Jia-Sheng
authors.initials: JS
authors.lastname: Wang
authors.forename: Jin-You
authors.initials: JY
authors.lastname: Lu
authors.forename: Ting-Ting
authors.initials: TT
authors.lastname: Li
authors.forename: Feng-Hu
authors.initials: FH
authors.lastname: Gao
authors.forename: Ping
authors.initials: P
authors.lastname: Zhou
authors.forename: Chuan-Ming
authors.initials: CM
authors.lastname: Zhu
authors.forename: Long-Zhu
authors.initials: LZ
authors.lastname: He
authors.forename: Bei-Bei
authors.initials: BB
authors.lastname: Yu
authors.forename: Shi-Qing
authors.initials: SQ
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002681:China; D004197:Disease Reservoirs / Q000469:parasitology*; D004777:Environment; D006801:Humans; D010571:Pest Control / Q000639:trends*; D045483:Rivers / Q000469:parasitology*; D012547:Schistosoma / Q000302:isolation & purification / Q000502:physiology; D012552:Schistosomiasis / Q000469:parasitology / Q000517:prevention & control*; D012621:Seasons; D012908:Snails / Q000254:growth & development* / Q000469:parasitology