[Investigation of natural foci of Metorchis taiwanensis in Wuhu area].

Objective: To explore the existence of natural foci of Metorchis taiwanensis in Wuhu area.
Methods: The ecological environment and daily living habits of residents were investigated; the eggs of M. taiwanensis in the dung of ducks in local region were collected by the sedimentation method; the Parafossarulus striatulus were disposed by the tabletting method and examined with a microscope to isolate the rediae and cercariae; the metacercariae in Pseudorasbora parve were isolated by using the homogenation. The duckling were fed directively by metacercaria of M. taiwanensis or by P. parve infected with metacercaria of M. taiwanensis for artificial infection, and M. taiwanensis were separated from ducks by dissecting the gallbladder and bile ducts.
Results: The survey revealed that there were staggered lake river, rich vegetation, overgrown shrubs, aquatic plants, rich variety of freshwater snails and fish resources in Wuhu area, and it was home to a variety of waterfowl and duck. The average detection rate of eggs of M. tanwanensis in stool of ducks was 33.33% (10/30); that of rediae and cercarriae in P. striatulus was 1.17%(7/600); and that of encysted metacercaria in P. parve was 13.33% (8/60); the number of M. taiwanensis detected in the infected ducklings in 3 groups were 31, 8 and 0, respectively, the natural M. tanwanensis infection rate of ducks was 23.33% (7/30).
Conclusion: We have confirmed the existence of natural foci of M. tanwanensis in Wuhu area.