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Worm Spit May Lick Liver Cancer

Thai liver worm in the bile ducts within the liver

A section of the Thai liver worm in the bile ducts within the liver, where it grows to adulthood and lives for decades. Credit: Prof Banchob Sripa

By Michael Smout

A liver worm is responsible for 26,000 cancer deaths every year, but a component in its spit could form the basis of a vaccine – and could even help to heal chronic wounds in diabetics.

The full text of this article can be purchased from Informit.

A hidden killer resides in the rural regions of north-eastern Thailand – a parasitic worm infection spread by eating uncooked fish. This parasite is the Thai liver worm (Opisthorchis viverrini), and it kills 26,000 people every year by inducing a deadly, mostly incurable liver cancer.

No cancer is ever good, but the variety of liver cancer the worm causes – cholangiocarcinoma ­– is especially aggressive and has a horrible life expectancy rating of 1. This means that a patient commonly won’t survive more than 1 year after diagnosis.

Opisthorchis causes cancer in one-sixth of infected patients. This is remarkable when compared with other high-impact cancer-causing pathogens such as the human papillomavirus, which causes cancer in less than 1% of infected individuals.

Opisthorchis predominantly infects the Isaan people of north-east Thailand, Laos and Cambodia, who share traditional meals of fermented (pla ra) or raw (koi pla) freshwater carp. (Don’t worry, your sushi/sashimi is safe from this parasite as ocean fish don’t get the infection.)

Although it will infect anyone who consumes the undercooked fish, three decades of Thai education campaigns and treatment programs have begun to limit infections to more remote regions and older generations who are resistant to change. Although these programs have only begun to move across borders,...

The full text of this article can be purchased from Informit.