A scoping review of malaria chemoprevention strategies and effectiveness among children under five in Africa.

Malaria remains a leading cause of morbidity and mortality among children under five in Africa. Chemoprevention strategies, including perennial malaria chemoprevention (PMC), seasonal malaria chemoprevention (SMC), together with other control measures, constitute a cornerstone of current preventive approaches. This scoping review aimed to synthesize evidence on the effectiveness of malaria chemoprevention strategies and to examine factors influencing their implementation across diverse epidemiological contexts. We systematically searched PubMed, Scopus, the Cochrane Database of Systematic Reviews, and Google Scholar for peer-reviewed quantitative studies published from 2002 to October 2025. Two reviewers independently screened records and extracted data using a standardized extraction form. Of 386 records identified, 42 met the inclusion criteria. Coverage across all doses ranged from 50% to 60% for both PMC and SMC, with adherence to the first dose consistently higher than for later doses. PMC showed a protective efficacy ranging from 20% to 87.5%, while SMC's protective efficacy reached 88.2%. Protection was markedly enhanced when chemoprevention was combined with malaria vaccination (RTS, S/AS01E). Effectiveness was modulated by transmission seasonality, prevalence of asymptomatic parasitemia, and local transmission intensity. Malaria chemoprevention is an effective strategy for reducing malaria burden in children under five, with the greatest impact observed when combined with vaccination.