Interactions tripartites entre le moustique Aedes aegypti, le virus de la dengue et les bactéries symbiotiques : état des connaissances et perspectives sur Delftia spp. et Chromobacterium sp.

Abstract

Dengue fever remains a global health priority, affecting over 390 million people annually and expanding across tropical regions. Vector control targeting Aedes aegypti remains essential due to the lack of specific antiviral treatment and the limited efficacy of current vaccines. In recent years, increasing attention has focused on the mosquito gut microbiota as a key determinant of vector competence. While Wolbachia has been extensively studied, other symbiotic bacteria such as Chromobacterium and Delftia spp. have emerged as promising candidates for biological dengue control. Chromobacterium produces bioactive compounds, including sphingolipids and antimicrobial metabolites, that inhibit dengue virus (DENV) replication. In contrast, Delftia spp., known for its antiparasitic activity against Plasmodium, may modulate mosquito immune pathways. This review summarizes recent advances on the interactions between these bacteria, the innate immune system of A. aegypti (Toll, Imd, JAK-STAT, RNAi), and DENV infection dynamics. It also highlights transcriptomic and functional approaches revealing the molecular mechanisms underpinning microbiota-mediated antiviral effects. Understanding these complex tripartite interactions could pave the way for innovative, sustainable symbiont-based strategies, particularly relevant in Africa where severe dengue outbreaks, such as the 2023 epidemic in Burkina Faso, underline the urgent need for locally adapted control measures.