Neglected tropical diseases

Fascioliasis: infection with the “neglected” neglected worms

12 March 09 | Geneva

An adult fasciola worm measuring 4.5cm. They can reach 7cm.
©Dr Albis Gabrielli/WHO

Millions of people are infected with fascioliasis and an estimated 180 million are at risk. People living in rural, agricultural villages in the Andean highlands of Bolivia and Peru have the highest rates of infection.

Fascioliasis – an infection of the liver caused by two trematodes (Fasciola hepatica and F. gigantica) – has existed since time immemorial.

It was always considered to be mainly a veterinary disease, and until the 1980s, only sporadic cases were reported in humans. More recently, its growing prevalence in human populations has prompted health authorities to address the problem effectively. Human fascioliasis is nowadays reported from more than 70 countries across the world.

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“Fascioliasis can cause serious complications in humans and can be treated with a safe, single dose of triclabendazole, made available free of charge by the pharmaceutical company Novartis. Treatment should be accompanied by advocacy and educational messages to avoid eating uncooked vegetables.”

Dr Dirk Engels, Coordinator PCT, WHO Department of Control of Neglected Tropical Diseases

Human infection occurs primarily through the ingestion of Fasciola larvae attached to raw or uncooked vegetables such as watercress or water mint, or floating in drinking water.

Human fascioliasis infection is successfully treated using a single dose of the drug triclabendazole. In case of treatment failure, two doses may be required, administered 12 hours apart.

WHO and Novartis Pharma AG have negotiated an agreement whereby Novartis will donate triclabendazole for the treatment of infected individuals in endemic countries. The drug will be available free of charge upon application from ministries of health. Countries as diverse as Bolivia, Egypt, Georgia, the Islamic Republic of Iran, Peru, Tajikistan, Viet Nam and Yemen already applied for donated triclabendazole and started treatment.

WHO invites ministries of health in affected developing countries to take advantage of this landmark donation programme. No continent is free from fascioliasis, and it is likely that where animal cases are reported, human cases also exist. Only with a reasonable triclabendazole stockpile will ministries of health be in a position (i) to supply their hospitals with enough drugs to allow their health staff to treat self-reported cases and (ii) to plan and implement large-scale drug distributions if fascioliasis is found to be an important public health problem.

How to apply for donated triclabendazole:

  • Make a rough estimate of how many people you aim to treat in a year. If you do not have data on the epidemiology and distribution of fascioliasis in your country, you can make a reasonable estimate by contacting the major hospitals and asking them how many cases they see per year.
  • Download the application form Annual Government request for triclabendazole [pdf 30kb]
  • Fill out the form, sign it and officially stamp it
  • Submit the application to the WHO Country Office with a covering letter, or
    fax it to + 41 22 791 4777, or e-mail it to:
  • If you already applied for donated triclabendazole in previous years, you should also download, fill out and send the report form Annual Report for Fascioliasis Control Activities
    [pdf 27kb]

If you need more information on the application please send an e-mail to:

More information:
Newsletter "Action against worms", special issue on fascioliasis, December 2007, Issue 10
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