Opisthorchis viverrini

Opisthorchis viverrini is a parasitic fluke that is endemic in Southeast Asia. It is one of the major causes of cholangiocarcinoma, a type of cancer that affects the bile ducts.

Life Cycle

The life cycle of Opisthorchis viverrini involves three hosts. The adult fluke resides in the bile ducts of the definitive host, which can be a human or a cat. The fluke produces eggs that are excreted in the feces of the host. These eggs are ingested by a snail, the first intermediate host. Inside the snail, the eggs hatch into larvae, which then develop into a stage called cercariae. The cercariae leave the snail and infect a fish, the second intermediate host. Inside the fish, the cercariae develop into metacercariae. When the fish is eaten raw or undercooked by a human or a cat, the metacercariae excyst in the duodenum and ascend the bile duct to mature into adult flukes.

Epidemiology

Opisthorchis viverrini is endemic in Southeast Asia, particularly in Thailand, Laos, Cambodia, and Vietnam. It is estimated that about 10 million people are infected with this fluke. The main risk factor for infection is the consumption of raw or undercooked fish.

Pathology

The adult flukes cause inflammation and fibrosis of the bile ducts, leading to cholangitis and cholecystitis. Chronic infection can lead to cholangiocarcinoma, a type of cancer that affects the bile ducts.

Prevention and Control

Prevention and control of Opisthorchis viverrini infection involve health education, improved sanitation, and control of the intermediate hosts. Treatment with the antihelminthic drug praziquantel is effective in eliminating the adult flukes.

See Also

• Cholangiocarcinoma
• Parasitic diseases
• Tropical diseases

• Opisthorchis viverrini
  Opisthorchis viverrini
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  Opisthorchis viverrini
• Opisthorchis viverrini egg
  Opisthorchis viverrini egg
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  Opisthorchis Life Cycle
• Chi River
  Chi River
• Thai fisherman
  Thai fisherman
• Koi pla
  Koi pla