Beyond Coverage: A Systematic Review and Thematic Analysis of Delivery, Compliance, Equity and Impact in Mass Deworming for Soil-Transmitted Helminths

Abstract

Purpose

Soil-transmitted helminth (STH) infections affect approximately 1.5 billion people globally. Although the World Health Organization (WHO) aims for 75% mass drug administration (MDA) coverage by 2030, the long-term population benefit remains debated. This review aims to describe the characteristics of recent mass deworming studies, synthesize parasitologic and coverage outcomes, and identify programmatic themes.

Methods

Search was conducted across Scopus, PubMed, and EBSCO CINAHL, restricted to studies reporting both parasitologic efficacy outcomes and MDA coverage. Following a risk of bias assessment in Review Manager 5.4, qualitative data were processed in Taguette 1.5.1 through a hierarchical thematic analysis to generate basic, organizing, and global themes and supplemented by VOSviewer 1.6.20 overlay visualization.

Results

Thirteen eligible studies primarily featured African countries and cross-sectional study designs. While overall risk of bias was low, lack of blinding revealed high performance bias. Thematic analysis, supported by bibliographic visualization, identified four global themes on delivery, compliance, equity and impact. Findings indicate that annual dosing is often insufficient and requires bi-annual schedules and WASH integration. Compliance is hindered by temporal inaccessibility and unreliable decentralized monitoring while equity gaps persist for out-of-school children and pregnant women. Although drug efficacy is confirmed, risks of resistance and diagnostic underreporting via the Kato-Katz method remain critical concerns.

Conclusion

This review identifies four interrelated pillars of delivery, compliance, equity, and impact that shape the effectiveness of mass deworming programs and have direct implications for achieving WHO 2030 targets.