Overview

• Santé publique France reports 570 autochthonous cases across 65 clusters as of September 22, up from 480 the previous week, marking an unprecedented level in metropolitan France.
• Antibes accounts for the largest cluster with 103 confirmed infections, prompting a rare FR‑Alert text to all residents on September 24 with protective guidance.
• Regional health agencies continue targeted insecticide spraying and door‑to‑door outreach while urging residents to eliminate standing water, use repellents, and seek care for fever, joint pain, or rash.
• PACA is the most affected region, and autochthonous cases have now been documented in new areas including Bourgogne‑Franche‑Comté, Centre‑Val de Loire, Grand Est, and Nouvelle‑Aquitaine; a recent case in Deux‑Sèvres led to overnight demoustication.
• Experts link the surge to the expanding Aedes albopictus range and warm, wet conditions that speed transmission, and note that vaccination plays a limited role as the Valneva shot faces U.S. suspension and a French contraindication for people over 65 pending review.