A Systematic Review and Meta-Analysis on the Top-Down Approach to Schistosomiasis Control and Elimination in Nigeria

Schistosomiasis continues to pose a significant public health challenge in Nigeria, particularly affecting morbidity rates among school-aged children and marginalized groups. In accordance with WHO guidelines, top-down strategies such as centrally coordinated Mass Drug Administration (MDA) and national control initiatives have been put into action. Nevertheless, the effectiveness and limitations of these strategies across various Nigerian contexts have not been thoroughly examined in a consolidated manner. A detailed systematic search was performed across databases including PubMed, Scopus, AJOL, and Google Scholar. Out of an initial 1,253 records, 328 duplicates were removed, and 925 titles and abstracts were evaluated. Ultimately, 114 full-text articles were analyzed, with 18 studies fulfilling the inclusion criteria for the systematic review and 12 providing adequate data for the meta-analysis. The eligibility criteria encompassed studies conducted in Nigeria that employed a top-down control approach and reported quantifiable schistosomiasis-related outcomes. The review indicated that top-down interventions like MDA significantly decreased the prevalence and intensity of schistosomiasis, with reductions observed between 40% and 70% in the majority of the studies included. However, systemic issues such as logistical shortcomings, inadequate community involvement, poor integration with WASH (Water, Sanitation, and Hygiene) strategies, and insufficient behavior change communication were frequently noted. The meta-analysis validated the statistical significance of these interventions but also highlighted variability in outcomes based on location and program fidelity. While top-down methods have resulted in substantial decreases in schistosomiasis prevalence in Nigeria, their long-term viability is jeopardized by structural and community-level implementation challenges. Enhancing decentralized health service delivery, fostering community-led initiatives, and ensuring collaboration across multiple sectors are crucial for meeting elimination goals by 2030.