Key Points

Chikungunya, Dengue, and Zika

Indigenous Cases

As of October 12, 2026, 26 outbreaks (+2 new outbreaks compared to the previous week) of locally transmitted vector-borne disease have been identified in mainland France:

• 22 outbreaks of chikungunya (+2 new outbreaks compared to the previous week), totaling 162 cases (1 to 34 cases per outbreak) in the Tarn, Lot, and Gard departments (Occitanie), in Gironde, the Landes, and the Pyrénées-Atlantiques (Nouvelle-Aquitaine), in Val-de-Marne (Île-de-France), and in the Var (Provence-Alpes-Côte d'Azur);
• 4 dengue outbreaks (no new outbreaks compared to the previous week) totaling 6 cases (1 to 2 cases per outbreak) in the Tarn, the Hérault (Occitanie), the Dordogne (Nouvelle-Aquitaine), and the Bouches-du-Rhône (Provence-Alpes-Côte d'Azur).

Investigations and prevention and control measures are underway for the various outbreaks that are still active.

Imported cases

From May 1, when enhanced surveillance began, through October 11, 2026, the following were identified:

• 159 imported cases of chikungunya
• 442 imported cases of dengue
• 17 imported cases of Zika

West Nile virus infections

Locally acquired cases

• As of October 12, 2026, 178 locally acquired cases of West Nile virus infection (+17 compared to the previous week) had been identified in mainland France. They are located in the Provence-Alpes-Côte d'Azur region (3 departments), Occitanie (7 departments), Île-de-France (7 departments), Auvergne-Rhône-Alpes (4 departments), Nouvelle-Aquitaine (Gironde department), Pays de la Loire (3 departments), Centre-Val de Loire (Loiret department), and Corsica (2 departments). For 17 cases, no specific site of infection could be identified. For one of these cases, it could not be determined whether the infection was autochthonous or imported.