Data and Code for the paper "Cost and cost-effectiveness of ivermectin mass drug administration for malaria control in Kwale County, Kenya"

Data and code corresponding to a decision tree cost-effectiveness analysis of malaria interventions in Kwale County, Kenya, conducted under the BOHEMIA (Broad One Health Endectocide-based Malaria Intervention in Africa) project. The shared dataset contains <b>aggregated variables</b> used to parameterize and reproduce the base case and sensitivity analyses reported in the associated manuscript.Due to confidentiality and ethical considerations, <b>raw data are not included</b>. Researchers interested in accessing the full raw dataset should submit a request to the BOHEMIA consortium, subject to data sharing agreements and ethical approval.The repository also provides the complete <b>R code</b> used for data cleaning, model construction, and analysis, ensuring transparency and reproducibility of the published results.Abstract:<br><b>Background: </b>Malaria remains a major health burden in sub-Saharan Africa, where traditional vector control methods face challenges like insecticide resistance and evolving mosquito behavior causing residual transmission. Ivermectin mass drug administration (iMDA), delivered in three monthly rounds with approximately 64% population coverage, was shown to reduce malaria incidence by 26% (95% CI, 5-42%, P=0.02) in a cluster-randomized trial conducted in Kenya. Using data collected during the trial, this study aims to assess the cost-effectiveness of iMDA as a supplementary vector control tool.<b>Methods: </b>A cost-effectiveness analysis of iMDA compared to a no-intervention scenario was performed, adopting a societal perspective on cost analysis. Intervention costs, health system costs, direct household out-of-pocket expenses, and indirect costs from lost wages were included. Effectiveness was measured as malaria cases averted and disability-adjusted life-years (DALYs) averted. A decision tree model was developed to simulate the intervention's impact on a broader population. Deterministic and probabilistic sensitivity analyses were performed to assess the robustness of the results, and Incremental Cost-Effectiveness Ratios (ICERs) were compared against Kenya’s GDP-based thresholds.<b>Findings: </b>The intervention cost of iMDA was $11·83 per person. Household out-of-pocket costs averaged $5·85 for uncomplicated malaria cases and $52·23 for severe cases. Productivity loss amounted to $2·18 for uncomplicated and $8·83 for severe cases. The base-case ICER was $905·23 per DALY averted, which falls below the threshold of 0·5Kenya’s GDP per capita ($974·65). In probabilistic analysis (10,000 iterations), the median ICER was US$1,107·51 per DALY averted (50% credible interval US$770·05–1,606·77).<b>Interpretation:</b> This study demonstrates that iMDA can be a cost-effective supplementary intervention for malaria control in settings with moderate malaria transmission and good insecticide treated net coverage, particularly when malaria reduction is greater than 23.6% for children under 5 and opportunities for reducing intervention costs can be identified.