[Expansion of the Asian tiger mosquito and associated arboviral diseases in Europe: effects of climate change and surveillance].

Abstract

The summer of 2025 and its historic chikungunya outbreak marked a turning point in the way we approach mosquito-borne viral diseases in Europe, and in particular those which depends on Aedes albopictus, the Asian tiger mosquito, for their transmission. These arboviral infections show a pronounced dependence on global change, owing to complex interactions between very different organisms. Mosquitoes, in particular, are highly sensitive to the effects of climate change. In this context, Aedes albopictus, an invasive species showing substantial adaptability and robustness, continues to expand across Europe, notably in Northern Europe. This mosquito is a key vector, in particular for dengue and chikungunya, whose clinical presentation is often non-specific, complicating diagnosis and the early detection of clusters. Faced with these complex characteristics, the challenge is to organize integrated surveillance that combines entomological monitoring, human surveillance, and adaptation to a situation that is, by its very nature, evolving. In Belgium, entomological surveillance (MEMO+) and mandatory case notification-structured differently across the country's entities-constitute essential yet still improvable pillars of this surveillance.