Global burden of intestinal parasites in children under five: a meta‑analysis

Background

Intestinal parasitic infections (IPIs) cause malnutrition, stunting, and increased mortality in young children, yet global prevalence estimates for the under-five population are fragmented. This review provides a contemporary global synthesis of IPI prevalence in children under five and examines key socioeconomic, environmental, and diagnostic determinants.

Methods

We systematically searched PubMed, Web of Science, Scopus, ScienceDirect, and Google Scholar up to November 2025 for cross-sectional studies reporting IPI prevalence in children <5 years. Pooled prevalence was estimated using a random-effects meta-analysis with the Freeman-Tukey double arcsine transformation. Subgroup analyses were performed by World Bank income level, Human Development Index (HDI), Global Burden of Disease region, climate, humidity, rainfall, and diagnostic method. Minor publication bias detected, assessed with Egger’s test, Begg’s test, and the Doi plot.

Results

Forty-one studies (15,109 children) were included. The global pooled prevalence was 31.60% (95% CI: 26.04–37.44%). Prevalence was highest in lower-middle-income countries (37.45%) and low-HDI regions (35.17%). South Asia (35.47%) and Eastern sub-Saharan Africa (35.24%) were major hotspots. Ascaris lumbricoides (11.93%) and Giardia lamblia (10.37%) were the most common parasites. Studies using direct smear plus ELISA reported significantly higher prevalence (57.09%) than single-method microscopy.

Conclusions

This study confirms an alarming burden of IPIs in children under five, driven by stark socioeconomic and environmental disparities. To effectively address this, we recommend that national surveillance systems in high-burden regions integrate highly sensitive diagnostic methods into their routine monitoring to accurately map high-risk areas. Public health actions should prioritize the hyper-localized combination of mass deworming campaigns with strengthened water, sanitation, and hygiene (WASH) infrastructure.

Key messages

• One in three children under five worldwide is infected with an intestinal parasite, with rates exceeding 50% in several low-income countries.

• Targeted public health actions combining mass deworming with improved sanitation and sensitive diagnostics are urgently needed in South Asia and sub-Saharan Africa.