Experimental study on controlling focus of paragonimiasis in diverting water engineering region

  Objective   To prevent Semisulcospira Liabertina from transmiting from the focus of paragonimiasis to other areas by diverting water, engineering was designed for controlling shell.The effects of the control engineering was studied.

  Methods   In the field, floating of Semisulcospira Libertina was tested.The experiment that the dam obstructed shell was made in 3 sites.

  Results   At conditions of still water, flowing water and rolling water, the Semisulcospira Libertina did not float at water and sank immediately.The shell crept to all direction on the river-bed before the dam.The lost rate of shell was very high.It was 91%, 97% and 86% separately.

  Conclusion   Because shell did not float, the control engineering of diverting top layer water of river was feasible for preventing shell from transmitting.The dam crossing river did not protect shell from transmitting.