Opisthorchis viverrini, a parasitic flatworm also known as the Southeast Asian liver fluke, causes opisthorchiasis, a disease affecting the liver and bile ducts. This parasite is prevalent in parts of Southeast Asia, including Thailand, Laos, Cambodia, and Vietnam, where consuming raw or undercooked freshwater fish is common. The parasite’s lifecycle involves fish-eating mammals, including humans, as definitive hosts and freshwater snails and fish as intermediate hosts.
Humans become infected by consuming fish containing the larval cysts (metacercariae) of Opisthorchis viverrini. Once ingested, the larvae migrate to the bile ducts and mature into adult flukes, where they can live for decades. While mild infections may be asymptomatic, chronic infections cause bile duct inflammation, abdominal pain, indigestion, and fatigue. Long-term infection increases the risk of serious complications such as bile duct stones, cholangitis (bile duct inflammation), and cholangiocarcinoma, a rare and aggressive form of bile duct cancer.
Treatment of opisthorchiasis typically involves the use of praziquantel, which is effective in killing the adult worms. Preventive strategies focus on avoiding the consumption of raw or undercooked fish, improving sanitation, and public education about the risks of eating contaminated fish. Preventing the disease is essential, as chronic infections can lead to severe health issues and economic burdens in affected communities.
