Overview

• ARS Île-de-France reported two autochthonous West Nile infections in Seine-Saint-Denis, marking the first local mosquito-borne cases in the Paris region.
• These northern transmissions follow five autochthonous West Nile cases recorded this summer in Provence-Alpes-Côte d'Azur, underscoring the virus’s geographic expansion.
• West Nile virus is carried from infected birds to humans by Culex mosquitoes and typically causes no or mild flu-like symptoms, though under 1% of patients can develop severe neurological complications.
• Health authorities have advised symptomatic individuals to seek immediate medical consultation and reinforced measures to eliminate standing water and install personal mosquito protections.
• Meanwhile, metropolitan France continues to face unusually high chikungunya and dengue clusters driven by Aedes albopictus and imported cases from recent outbreaks in La Réunion and Mayotte.