Effectiveness and implementation contexts of water, sanitation, and hygiene (WASH) interventions in Anglophone sub-Saharan Africa: a scoping review

Abstract

Sub-Saharan Africa (SSA) has the world's lowest coverage of safely managed water, sanitation, and hygiene (WASH) services. Numerous global and pan-African systematic reviews exist, but often has limited applicability to this sub-region. This scoping review maps the effectiveness and outcomes of WASH interventions implemented since 2010 in 17 Anglophone SSA - countries. Following JBI methodology and PRISMA-ScR guidelines, through searches of four databases (PubMed, Scopus, Google Scholar, and ResearchGate) and websites of relevant WASH organizations from July to December 2023. Two reviewers independently screened 523 unique records screened, 51 publications reporting 49 interventions. Most interventions (71%) combined all three WASH components and were delivered in rural areas (74%) via community- or school-based platforms. RCTs comprised (76%) of the study design. About 78% of interventions achieved increased latrine coverage, handwashing with soap, or reduced diarrhoeal/helminth infections. Major enablers were community ownership, participatory design, and sustained engagement. Dominant barriers were financial constraints, delayed funding, poor adherence and weak political/institutional support.Equity analyses were rare and showed mixed or pro-rich effects. By focusing exclusively on Anglophone SSA and systematically analyzing contextual and equity dimensions, this review provides implementation-focused evidence to inform more effective, equitable, and sustainable WASH policies.