Parasites - Clonorchis

Clonorchis is a liver fluke parasite that humans can get by eating raw or undercooked fish from areas where the parasite is found. Found across parts of Asia, Clonorchis is also known as the Chinese or oriental liver fluke. Liver flukes infect the liver, gallbladder, and bile duct in humans. While most infected persons do not show any symptoms, infections that last a long time can result in severe symptoms and serious illness. Untreated, infections may persist for up to 25–30 years, the lifespan of the parasite.

Diagnosis of Clonorchis infection is based on microscopic identification of the parasite’s eggs in stool specimens. Safe and effective medication is available to treat Clonorchis infections. Adequately freezing or cooking fish will kill the parasite.

Images: Left: Adult of C. sinensis, stained with carmine. Right: C. sinensis egg in a fecal sample. (Credit:  DPDx)