Distribution: Often referred to as "The Chinese Liver Fluke", Clonorchis sinensis is found in most of China and South-East Asia, Japan, Korea, Russia, and Taiwan. 7 million people are believed to be infected by C. sinensis11.
General Distribution of C. sinensis 10
Description: This fluke has a very similar lifecycle, digestive system, and morphology to O. viverrini, but it is somewhat larger. Adults are gray in color and 10-25 mm by 3-5mm. The gut is bifurgated, a characteristic of all flukes, and the ventral sucker is smaller than the oral sucker. Like O. viverrini, C. sinensis is hermaphroditic, but O. viverrini differs in its highly branched testes (Clonorchis: klonos=branch, orchis=testes). The ovary is small and eggs are approximately 30 x 15 microns in size. The life span can be up to 25-30 years11.
Association with Malignancy: Numerous case studies, beginning around 1956, have shown infection with C. sinensis to be correlated with increased rates of intrahepatic bile-duct tumors and cholangiocarcinoma. A case-control study of Chung and Lee showed C sinensis infection did not effect the risk of hepatocellular carcinoma, but increased the incidence of cholangiocarcinoma sixfold11.
Infection with C. sinensis 10
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