Axis 1

This axis aims to better understand the ecological and evolutionary determinants shaping the circulation of infectious agents in island ecosystems of the southwestern Indian Ocean. The geographical location of La Réunion, within an emergence hotspot, enables the implementation of long-term monitoring programs allowing to decipher natural infection cycles, identify conditions favorable to emergence events, and assess zoonotic risks. Research focuses specifically on the interactions between vertebrate reservoirs, arthropod vectors and pathogens, as well as on the impact of global changes on infectious dynamics.

Research activities rely on integrated field surveys targeting bats, small mammals, birds and haematophagous arthropods (e.g. mosquitoes, ticks, fleas). investigated agents include viruses with high emergence potential (Corona-, Paramyxo-, Influenza-viruses, etc.) as well as zoonotic bacteria (Leptospira spp., Yersinia pestis). Experimental facilities, including the PLATIN-OI platform, are used to assess the transmission capacity of occurring mosquito species for endemic or emerging arboviruses. These studies combine metagenomics, transcriptomics, phylodynamics and spatio-temporal modelling to better understand the ecology of reservoirs and vectors, measure the effects, for instance, of urbanisation, climate change or the introduction of exotic species on infectious dynamics, and identify cross-species transmission events at the animal–human interface.