Key Points

Dengue, Chikungunya, and Zika

• Since the last bulletin, we have learned of a new outbreak of locally transmitted chikungunya in the Alpes-Maritimes department. The case spent the period of exposure in the municipalities of Grasse and Saint-Vallier-de-Thiey.

• Additionally, the epidemiological situation in Fréjus has changed since the last bulletin, with a second area of transmission identified in the municipality. As of August 19, there are 7 cases. In the municipalities of Vitrolles and Antibes, several suspected cases have been confirmed, bringing the total to 33 cases (+10) and 7 cases (+3), respectively.

• As of August 19, the PACA region has recorded 12 episodes of local transmission: 9 of chikungunya and 3 of dengue. In total, 66 local cases of chikungunya (+17) and 6 local cases of dengue have been identified.

• Since the start of enhanced surveillance (May 1), 182 imported cases (+4 since the last update) have been identified in the region: 94 cases of dengue, 91 of chikungunya, and 1 case of Zika.

West Nile Virus Infections

• Since the last bulletin, 4 new cases of West Nile virus (WNV) infection have been reported: 3 in Bouches-du-Rhône and 1 in Vaucluse.

• As of August 19, the Provence-Alpes-Côte d’Azur region has recorded 9 cases of WNV infection: 3 in the Var department, all in the municipality of Hyères, and 5 cases in the Bouches-du-Rhône department, including 3 in the municipalities of Salon-de-Provence and Grans.

Heat Wave

• A heat wave occurred in the Provence-Alpes-Côte d’Azur region from August 9 to 19, 2025, with all departments in the region placed under an orange heat wave alert.

• Analysis of regional emergency care utilization during the heat wave indicates stable activity levels for the iCanicule indicator from the SOS Médecins associations and hospital emergency departments.