Characteristics of clonorchosis foci in north Viet Nam

The article analyzes the results of studies on the first and second intermediate hosts of the clonorchosis pathogen in mountainous and coastal provinces of Northern Vietnam. Habitats of mollusks of the family Bythiniidae of the first intermediate hosts of Clonorchosis sinensis are identified. Infestation by C.sinensis larvae was detected only in clams Parafossarulus striatulus in Thác Bá reservoir 0.1% of cases. Infestation of fish with cysts of this trematode was found in 6 of 12 studied provinces. The most favorable conditions for the formation and functioning of clonorchosis foci are created in the floodplain of the Hôngkha River and its tributaries in the central and coastal provinces of North Vietnam.

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