While virtually nonexistent and unheard of in developed countries today, parasitic worm infections are endemic in many of the poorest countries in the world.
These infections, known as soil-transmitted helminths (STH) and schistosomiasis, interfere with nutrient uptake, and can lead to anemia, malnourishment, and impaired mental and physical development. They pose a serious threat to children’s health, education, and productivity. Infected children are often too sick or tired to concentrate at school, or to attend at all.
Worm infections disproportionately affect the poor. They are easily transmitted in areas with poor sanitation and open defecation. Children are particularly susceptible.
Parasitic worms exact an enormous toll on human capital, slowing economic development in parts of the world that can least afford it.
Treatment with a simple pill is universally recognized as a safe and simple solution. Evidence Action's Deworm the World Initiative focuses on treatment delivered through existing school infrastructure. This is highly cost-effective and accepted well by communities, and able to reach hundreds of millions of children.
Rigorous evidence shows that school-based deworming programs can improve health and education outcomes for children at a cost of less than $0.50 per year.
In November 2016, GiveWell named the Deworm the World Initiative at Evidence Action one of its top-rated charities for a fourth year in a row, stating that it is recommended as "a program with a strong track record and excellent cost-effectiveness."
The Abdul Latif Jameel Poverty Action Lab at MIT lists mass school-based deworming as a “best buy" in both education and health. Similarly, the Copenhagen Consensus recommends treating children when they are in school, citing research that notes that "in countries where many people are infected, the benefits of deworming can be up to 60 times higher than the costs."
The Deworm the World Initiative envisions a world where all at-risk children have improved health, increased access to education, and better livelihoods potential as a result of being free of intestinal worms.
We advocate with governments to launch deworming programs, then work collaboratively with them to establish effective policies and long-term commitment by building their capacity, mobilizing domestic support and sharing global best practices to improve cost-effectiveness and results.
We work with governments and communications experts to design locally appropriate awareness campaigns to communicate messages through a wide variety of channels to increase public acceptance and effectiveness of deworming programs.
We help governments evaluate appropriate drug treatment strategies and dosage, support drug procurement including through global pharmaceutical donation programs, and design robust serious adverse event protocols and drug tracking systems.
We work with epidemiologists and local partners to assess worm prevalence and intensity, obtaining data to develop a targeted treatment strategy and to determine the impact of programs once they are in place.
We help governments design monitoring systems to measure effectiveness in achieving intended program objectives. We also conduct independent monitoring to validate program results, and evaluate the impact of programs in reducing worm prevalence and intensity.
We work closely with ministries of education and health to design a program with joint ownership, develop operational plans and budgets, coordinate logistics, and provide on-the-ground support to ensure a high quality outcome.
We consistently design and support training through an efficient multi-tier cascade approach that is tailored to the local context, ensuring knowledge reaches from the national level all the way to the teachers responsible for administering deworming medication.
Parasitic worms are debilitating, widespread, and under-treated. School-based deworming is safe, cost-effective and scale-able. What is the evidence base for the work that the Deworm the World Initiative undertakes?
We summarize the evidence base for mass school-based deworming programs in this post. Here are key findings across the key impacts of deworming: school participation, future earnings, and cognition and nutrition.
Miguel and Kremer’s experimental evaluation in Western Kenya found a 25% reduction in student absenteeism at treatment schools.
Baird and colleagues’ long-run study based on the Western Kenya deworming finds that among females, deworming increased the rate of passing the national primary school exit exam by 9.5 percentage points on a base of 41%.
“Does Mass Deworming Affect Child Nutrition?: Meta-analysis, Cost-Effectiveness, and Statistical Power” authored by Kevin Croke, Joan Hamory Hicks, Eric Hsu, Michael Kremer, and Edward Miguel, finds a “substantial” and “highly robust” positive effect on child weight resulting from deworming. The effects are particularly large in areas above 20% prevalence; this is the same threshold at which the WHO currently recommends mass treatment. The authors also note the cost-effectiveness of deworming, with "the estimated average weight gain per dollar expenditure from deworming...more than 35 times that from school feeding programs as estimated in RCTs."
A randomized health intervention that provided iron, Vitamin A and deworming drugs to Indian preschool children in poor areas of Delhi found a significant gain in child weight and school participation compared to intervention with Vitamin A alone. Absenteeism was reduced by one-fifth in the treatment group. We do note, however, that the large DEVTA trial found no impacts of deworming or Vitamin A supplementation on mortality in a rural area where worm loads were light. We prioritize, and urge our government partners to prioritize, investment in areas where worm loads are high.
A randomized controlled trial in Uganda (Alderman and colleagues, 2006) finds that the provision of periodic anthelmintic treatment as a part of child health services resulted in an increase in weight gain of about 10% above expected weight gain when treatments were given twice a year, and an increase of 5% when the treatment was given annually.
Chronic infections in childhood (from diarrhea, to malaria, to worms) generate inflammatory (immune defense) responses lead substantial energy to be diverted from growth. There are interaction effects too, with deworming, for example, making it easier to fight off malaria. More generally, in their summary of deworming, the WHO points to several channels by which worms may impair nutrition, and notes several studies that can support these claims.
Is mass treatment justified? On cost-effectiveness grounds we believe that it clearly is, as the cost of treatment is cheaper than individual screening. The WHO states that the cost of screening is four to ten times that of the treatment itself. Because the drugs are very safe and has no side effects for the uninfected, the WHO does not recommend individual screening. The WHO instead recommends mass drug administration in areas where more than 20% of children are infected.
Deworming through schools, and preschools in some areas, provides the greatest opportunity to reach a high proportion of the at-risk population while minimizing costs through the use of existing government infrastructure.
Evidence Action’s Deworm the World Initiative has ambitious plans in the next several years to eliminate the public health threat of parasitic worms. We are poised to take advantage of an unparalleled window of opportunity to rapidly accelerate treatment coverage of children worldwide.
Multilateral organizations, pharmaceutical companies, NGOs, and governments are prioritizing the elimination of neglected tropical diseases, allocating resources and developing roadmaps for scaling up treatment.
We are helping put deworming and a world free of worms on the global agenda.
Accelerating treatment to cover the at-risk school-age children in the highest-burden countries is the most cost-effective and efficient way to achieve the WHO goal of 75% coverage of school-age children.
This is where we focus.
The Deworm the World Initiative scales school-based deworming in these high-need geographies.
We have expanded our technical assistance support to a national school-based deworming program in India and Ethiopia, and started work in Nigeria and Vietnam, while maintaining technical support in Kenya and states in India were we have previously worked.
Thrive Networks is our partner in Vietnam. The program there supports deworming in four provinces. The program has achieved over 90% coverage in its first round of treatment this year with another round underway at the end of 2016. We are also planning an RCT to evaluate the effects of a hygiene intervention on worm infections in 2017.
We’re entering our fifth year at national scale in Kenya. The Government of Kenya’s National School Based Deworming Program routinely treats ~ 6 million children for both STH and schistosomiasis. Year 3 results were released during the first week of March 2016 in this booklet. 6.1 million children were treated. Year 4 results will be released in early 2017.
In Ethiopia, we partner with the Schistosomiasis Control Initiative (SCI) in supporting the Federal Ministry of Health’s national school-based deworming program. The program is projected to distribute over 100 million deworming treatments to school-age children over the next five years.