Epidemiology and Control of Soil-Transmitted Helminth Infections

Soil-transmitted helminth infections remain among the most pervasive neglected tropical diseases, affecting more than a billion people worldwide. The principal species—Ascaris lumbricoides, Trichuris trichiura and the hookworms Necator americanus and Ancylostoma duodenale—are acquired via contact with faecally contaminated soil. Heavy infections compromise nutritional status, impair cognitive development in children and exacerbate anaemia. Control efforts have centred on preventive chemotherapy through periodic administration of benzimidazole drugs, often delivered via school-based or community-wide mass drug administration (MDA) campaigns. These interventions can rapidly reduce worm burden but do not prevent reinfection, which often occurs within months in high-transmission settings. Complementary measures in water, sanitation and hygiene (WASH) are essential to interrupt transmission, yet implementation and uptake vary widely. Emerging challenges include the potential evolution of drug resistance under recurrent deworming, gaps in monitoring efficacy and low coverage among marginalised populations. Integrated strategies that combine targeted chemotherapy, reinforced sanitation infrastructure, health education and novel therapeutic agents are now viewed as critical to achieving sustainable reductions in disease burden and moving towards elimination in vulnerable regions.

Research from Nature Portfolio

Recent modelling work employing individual-based simulations has shed light on the dynamics of benzimidazole resistance in human soil-transmitted helminths. Under current school-targeted preventive chemotherapy strategies, resistance alleles could increase to detectable levels within a decade, particularly where community-wide deworming is practised without systematic monitoring of drug efficacy. The study emphasises that intensifying coverage accelerates parasite elimination but simultaneously exerts stronger selective pressure for resistance. It calls for routine surveillance of anthelmintic performance, incorporation of resistance management principles and exploration of combination regimens to prolong the useful lifespan of existing drugs. This approach provides a quantitative framework to optimise the balance between rapid morbidity control and mitigation of resistance risk.

Epidemiology and Control of Soil-Transmitted Helminth Infections publication trend

The graph below shows the total number of articles in epidemiology and control of soil-transmitted helminth infections across all publications each year (not limited to Nature Index journals).

Technical terms

Soil-transmitted helminths (STHs): Parasitic nematodes transmitted through contact with soil contaminated by human faeces, including Ascaris, Trichuris and hookworm species.

Preventive chemotherapy: Scheduled administration of anthelmintic medications to at-risk groups to reduce infection intensity and related morbidity.

Benzimidazoles: A class of broad-spectrum anthelmintic agents (such as albendazole) widely used in mass deworming programmes.

Mass drug administration (MDA): Distribution of anthelmintic treatment to entire populations or defined risk groups, irrespective of individual infection status.

Individual-based model: A computational framework that simulates infection, treatment and resistance processes at the level of individual hosts to predict population-scale outcomes.

References

1. Efficacy and safety of emodepside compared with albendazole in adolescents and adults with hookworm infection in Pemba Island, Tanzania: a double-blind, superiority, phase 2b, randomised controlled trial. The Lancet (2024).
2. Predicting the risk and speed of drug resistance emerging in soil-transmitted helminths during preventive chemotherapy. Nature Communications (2024).
3. Protective efficacy of short-term infection with Necator americanus hookworm larvae in healthy volunteers in the Netherlands: a single-centre, placebo-controlled, randomised, controlled, phase 1 trial. The Lancet Microbe (2023).
4. Deworming and micronutrient status by community open defecation prevalence: An observational study using nationally representative data from India, 2016–2018. PLOS Medicine (2024).
5. Global numbers of infection and disease burden of soil transmitted helminth infections in 2010. Parasites & Vectors (2014).
6. Water, Sanitation, Hygiene, and Soil-Transmitted Helminth Infection: A Systematic Review and Meta-Analysis. PLOS Medicine (2014).
7. Soil-Transmitted Helminth Reinfection after Drug Treatment: A Systematic Review and Meta-Analysis. PLOS Neglected Tropical Diseases (2012).