Evaluating effectiveness of protective interventions towards environmental contamination among under-five children: systematic review and meta-analysis in Africa

Under-five children have a high vulnerability to environmental contaminants for gastrointestinal tract (GIT), respiratory tract, and skin problems. Effective protective interventions on such cases built future healthy and productive generation. The objective of this review and meta-analysis was evaluating the effectiveness of studies done under protective interventions in reducing environmental contaminants among children of under-five in African countries. Comprehensive searches were carried out across multiple databases like PubMed, MEDLINE, Cochrane Library, CINAHL, Science Direct, and Web of Science. Searches added from Google search, Google Scholar, African Journals Online (AJOL), and references list until June 30,2025. A PRISMA 2020 flow diagram was used for systematic review. A random-effect model was used to estimate the pooled effect size of the Risk ratio. Heterogeneity was evaluated using I 2 , Cochrane Q-test and p -value. Sensitivity test and subgroup analysis had been done in the evaluation of protective intervention data. Besides, publication bias was checked. Twenty-seven studies were considered in the systematic review like cohort, case control, experimental studies and eleven RCT studies were included for pooled meta-analysis. Overall pooled effect size of effectiveness of protective interventions on environmental contamination was 59%, I 2 82.2%. The subgroup analysis by study periods greater than twelve months effect size estimates were 56.28%, and p -value 0.0001. This review evaluating Protective interventions of studies on environmental contaminations among children of under-five in Africa from 2015 to 2024. The meta-analysis identified different protective interventions strategies of WASH-based play yard, improved latrine, safe child feces disposal, treated drinking water at point of use, hand washing with soap at critical time, separated and ventilated kitchen, improved cook stove. Except for skin-related cases having limited interventions, our evaluation on the effectiveness of protective interventions of studies remarkably reduced children’s exposure to environmental contamination. More study efforts were needed on such regard.