e-Library of Evidence for Nutrition Actions (eLENA)


An online library of evidence-informed guidelines for nutrition interventions and single point of reference for the latest nutrition guidelines, recommendations and related information.

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Deworming in non-pregnant adolescent girls and women of reproductive age

Intervention | Last updated: 20 June 2023


Soil-transmitted helminth infections are among the most common infections in humans, caused by a group of parasites commonly referred to as worms, including roundworms, whipworms and hookworms. Those living in poverty are most vulnerable to infection which can impair nutritional status by causing:

  • internal bleeding which can lead to loss of iron and anaemia;
  • intestinal inflammation and obstruction;
  • diarrhoea; and
  • impairment of nutrient intake, digestion and absorption.

Evidence shows that preventive chemotherapy, or the periodic large-scale administration of anthelminthic medicines to populations at risk, can dramatically reduce the burden of worms caused by soil-transmitted helminth infections.

Preventive chemotherapy is an important part of a comprehensive package to eliminate morbidity due to soil-transmitted helminths in at-risk populations. However, long-term solutions to soil-transmitted helminth infections will need to address many factors, including improvements in water, sanitation and hygiene.

WHO Recommendations


Preventive chemotherapy (deworming), using annual or biannuala single-dose albendazole (400 mg) or mebendazole (500 mg), is recommended as a public health intervention for all non-pregnant adolescent girls and women of reproductive age living in areas where the baseline prevalence of any soil-transmitted helminth infection is 20% or more among adolescent girls and women of reproductive age, in order to reduce the worm burden of soil-transmitted helminths.

a Biannual administration is recommended where the baseline prevalence is more than 50%.



Cost-effectiveness Learn More Alternate Text


Systematic reviews


Cost and cost-effectiveness of soil-transmitted helminth treatment programmes: systematic review and research needs

Turner HC, Truscott JE, Hollingsworth TD, Bettis AA, Brooker SJ, Anderson RM. Parasit Vectors. 2015; 8:355.


Cost-effectiveness analyses


Weekly iron-folic acid supplementation with regular deworming is cost-effective in preventing anaemia in women of reproductive age in Vietnam

Casey GJ, Sartori D, Horton SE, Phuc TQ, Phu LB, Thach DT, et al. PLoS One. 2011; 6(9):e23723.