STH has major negative health and developmental impacts on endemic communities

Reducing soil-transmitted helminthiasis (STH) infections, commonly known as intestinal worm infections, and their effects is vitally important to the more than one billion people at risk of infection. Approximately 875 million of those at risk of STH are children. Endemic in more than 100 countries, STH is the most common parasitic infection globally. 

STH is a disease of poverty, affecting the poorest and most vulnerable people on earth. Repeated infections, leading to infected individuals harboring a large number of worms, have major health impacts on children and women of childbearing age. STH diminishes absorption of vital nutrients, jeopardizing long-term health while preventing infected individuals from reaching their full potential. Infections can cause anemia, intestinal obstruction, rectal prolapse, stunted growth, and impaired cognitive development. 

When a person is infected with intestinal worms, they suffer as does the larger community. Children may perform poorly at school resulting from their symptoms, which in turn leads to decreased economic productivity later in life. Stated simply, STH undermines the health and economic development of endemic communities. 

Safe and effective interventions exist to control STH

Known interventions for STH are safe and effective. The drugs used for preventive chemotherapy to control STH, primarily albendazole and mebendazole, effectively reduce infection intensity and often, in the case of albendazole for hookworm and mebendazole for Ascaris, can eliminate infection altogether. Over approximately a  decade, close monitoring of drug treatments, involving millions of children in multiple countries, demonstrates that these drugs are safe and have minor or no side effects.2 

Medicines to treat STH are available largely because of the generous donations by GlaxoSmithKline3 and Johnson & Johnson. Collectively, the companies have committed themselves to donate 600 million treatments per year through 2020. These generous donations have underpinned global control efforts to-date.

The treatment of entire at-risk communities (i.e. mass drug treatment) is the primary available means to delivery preventive chemotherapy to endemic communities. As recommended by the World Health Organization, CWW supports mass drug treatment, as opposed to only treating infected individuals, for the following reasons:

  • Large numbers of people harbor one or more STH species in endemic areas.
  • Diagnostics, which would be necessary for treating only infected individuals, are difficult, expensive, and time-consuming to perform.
  • The drugs are safe and effective even when taken by non-infected individuals.

CWW understands the components and intensity of intervention delivery necessary to reduce and stop infections, but the resources to deliver these interventions, including WASH, are limited. Only 48% of the 269 million preschool age children (1-4 years old) and 63% of the 572 million school age children (5-14 years old) received preventive chemotherapy in 20154. More resources and attention are needed to end the health effects of intestinal worms. CWW exists to address, and help others address, the key technical, informational, programmatic, and coordination gaps that result in intervention coverage gaps and undermine effective STH control efforts in all endemic countries.


2Loukas A, Hotez P. Chemotherapy of helminth infections. In: Brunton L, et al., eds. Goodman and Gilman’s The pharmacological basis of therapeutics, 11th ed. New York, McGraw-Hill; 2006. 

3GLAXOSMITHKLINE, GSK and the GSK Logo are trademarks of the GSK group of companies and are used with the permission of GSK.

4World Health Organization. Weekly Epidemiological Record. 30 September 2016, vol. 91, 39.



STH is complex and challening, but, together, we have the power to create healthier communities with brighter futures by reducing intestinal worm infectiosn. CWW, with its partners, is committed to a world free from the efffects of STH.