Clonorchiasis is an infectious disease caused by the Chinese liver fluke (Clonorchis sinensis) and two related species.

The water snail is the first intermediate host, in which a miracidium (an embryonated egg discharged in stool) goes through its developmental stages (sporocyst, rediae and cercariae).

[7] Adult C. sinensis worms can inhabit the bile ducts of humans for 20–25 years without any clear clinical symptoms.

[9] The WHO recommends a combination of veterinary public health measures, education of food safety practices, and expanding access to anthelminthic drugs.

The European Union (EFSA) specifically require an extended time for fish suspected of containing Clonorchis or Opisthorchis compared to other parasites.