Key Points

Local Cases

• As of June 24, 2025, we have identified six episodes of local transmission of chikungunya in mainland France (n = 8 cases). These episodes are located in regions already affected by episodes of local transmission in previous years: Provence-Alpes-Côte d'Azur, Corsica, Occitanie, and Auvergne-Rhône-Alpes. Investigations and prevention and control measures are underway.

• Such an early start to the mosquito season and such a high number of outbreaks had never been observed before.

• Although declining, the number of chikungunya cases among travelers to Réunion and the Indian Ocean remains high and contributes to the early onset of local transmission.

• Santé publique France emphasizes the importance of reporting cases, which enables rapid intervention to limit local transmission, as well as the importance of measures to protect against mosquito bites and control breeding sites.

Imported cases

From May 1, the start of enhanced surveillance, through June 24, 2025, the following were identified:

• 454 imported cases of dengue

• 645 imported cases of chikungunya

• 1 imported case of Zika