Systematic review on the cost of seasonal malaria chemoprevention (SMC).

Background: Implemented in 17 countries to date, seasonal malaria chemoprevention (SMC) is a recommended strategy to prevent childhood malaria in areas with seasonal transmission of P. falciparum through monthly administration of antimalarial medicines. Understanding the costs and resource requirements of SMC delivery is necessary for effective planning and resource allocation. This systematic literature review aims to assess the evidence on the cost and cost-effectiveness of SMC delivery.

Methods: Following PRISMA guidelines, five databases were systematically reviewed to identify evidence on SMC costs and cost-effectiveness published between 2012 and 2023. Studies with defined costing methodologies and cost output measures were included, excluding those relying solely on mathematical modeling. Two reviewers assessed each study for eligibility and extracted cost data, which were adjusted for inflation. Quality assessment was completed using the CHEERS checklist.

Results: Six costing studies were identified spanning nine countries. Four studies examined costs during an SMC pilot or introduction, one during scale-up, and one costed newly established SMC campaigns through a multi-country project. Costs were examined at country level with the financial costs per child receiving a full course of SMC ranging from $1.71 to $12.46, while economic costs per child ranged from $2.11 to $29.06. Four studies included a cost effectiveness analysis with incremental cost-effectiveness ratios (ICERs) per clinical malaria case averted ranging from $5.41 to $138.03; ICER per disability-adjusted life year (DALY) averted from $24.51 to $182.88; and ICER per death averted from $688.86 to $18,418.81. Differences in cost estimates stemmed from different factors including variations in cost ingredients, scale of the intervention, and study perspectives.

Discussion: The level of detail for reporting SMC costs and cost categories varied greatly by study as did the scale of intervention, limiting comparability as well as an understanding of the complete costs and resource requirements for SMC implementation. Cost evidence is not from mature programs but from pilots or relatively new campaigns. Costs incurred by households and costs of the integrated delivery of SMC with other health interventions were often overlooked. Adopting a standardized costing approach for mature SMC programmes could provide a better understanding of resource requirements and costs while enhancing study comparability across settings, better informing future resource allocation and improving efficiency.