Strengthening insecticide resistance management in malaria vectors control in Côte d’Ivoire: from evidence to action

Abstract

Malaria remains a major public health challenge in Côte d’Ivoire, particularly among young children and pregnant women. Insecticide-treated nets (ITNs) have significantly reduced transmission, but their effectiveness is increasingly threatened by widespread insecticide resistance in malaria vectors. In response, Côte d’Ivoire developed a national insecticide resistance management (IRM) plan (2017–2020) to preserve the effectiveness of vector control interventions. This review examined coherence between planning and practice, the responsiveness of strategies to emerging resistance trends, and the integration of resistance management into broader malaria control efforts. To characterize the interventions implemented under the IRM plan and their impact on the targeted outcomes a mixed-methods approach was used. This included document reviews, analyses of epidemiological and entomological data, and interviews with key stakeholders and subject matter experts. Key achievements included the stratified deployment of insecticide-treated nets (ITNs), limited implementation of indoor residual spraying (IRS), and pilot larval source management (LSM). Resistance to pyrethroids, carbamates, organochlorines and organophosphates was found to be widespread across the country. Indeed, nine studies conducted across 54 localities in Côte d’Ivoire reported mortality rates below 80% to these insecticides. Furthermore, resistance to newer insecticide classes such as neonicotinoids and pyrroles was also detected in certain localities. Funding constraints emerged as a major barrier, resulting in gaps in implementation and delayed activities. This case study shows that although progress has been achieved in term of vector control strategies, and strengthened entomological surveillance, current interventions remain insufficient to keep pace with the spread of resistance. Some limitations can be highlighted after IRM implementation. The study relied on secondary data sources, national reports, and stakeholder interviews, with no direct entomological field assessments or efficacy trials, and was further constrained by the absence of a comprehensive national entomological database, which may have introduced reporting bias and limited the depth of resistance trend analysis. Côte d’Ivoire’s experience provides lessons for other malaria-endemic countries facing similar insecticide resistance challenges.