Prevalence and Determinants of Never Treatment During Mass Drug Administration for Lymphatic Filariasis: A Systematic...

The term "never treated" refers to individuals who self-report having never ingested tablets during any round of Mass Drug Administration (MDA) against Lymphatic Filariasis (LF). This study estimated the pooled prevalence of never-treated individuals with MDA for LF and identified factors associated with persistent non-treatment.

This systematic review and meta-analysis was registered in PROSPERO [CRD420251270067] and conducted in accordance with the PRISMA 2020 guidelines. Relevant literature was identified by searching databases, i.e., PubMed, Scopus, Cochrane Central, Embase, Web of Science, and Epistemonikos from January 2000 to December 2025, and only studies published in English were included. The AXIS tool was used to assess the study quality. A random-effects model with 95% CI was applied to estimate the pooled prevalence. Subgroup, leave-one-out sensitivity, and meta-regression analyses were conducted to explore the heterogeneity.

Eighteen studies including 24,940 individuals showed the pooled prevalence of never treatment during all MDA rounds at 26% (95% CI: 16% to 37%, I² = 99.7%, 95% prediction interval: 0% to 75%). Exploratory subgroup analysis indicated wide regional and MDA round-specific variations. Meta-regression indicated that publication year did not explain the variability. Common reasons for persistent non-treatment included fear of side effects, limited knowledge, difficulty swallowing the pills, and absence during drug distribution.

Persistently never-treated populations may represent an important programmatic barrier to LF elimination. Given the very low certainty of evidence, extreme heterogeneity, and potential publication bias, these estimates should be interpreted cautiously. Future research should ensure broader geographical representation, including both urban and rural areas, and explore structural, behavioural, and socio-cultural determinants to better target high-risk groups.