Key Points

Chikungunya, Dengue, and Zika

• A first indigenous outbreak of chikungunya has been identified and investigated in Corsica in the municipality of Grosseto-Prugna (Southern Corsica). Three cases linked to this outbreak have currently been identified.

• At the same time, nine outbreaks of locally transmitted chikungunya cases (an increase of 3 since the last update) and a first locally transmitted dengue outbreak have been identified on the mainland. The number and early onset of these outbreaks in mainland France confirm the very high risk of numerous areas of local transmission in 2025.

• Since the start of enhanced surveillance (May 1), 3 imported cases of dengue (no new cases compared to last week) and 3 imported cases of chikungunya have been confirmed (no new cases compared to last week).

Extreme heat, heat wave

• The heatwave, which began on June 27, ended on Sunday in Haute-Corse and on Monday in Corse-du-Sud.

• The regional analysis of emergency care utilization indicates that the iCanicule health indicator (including medical diagnoses of hyperthermia/heatstroke, dehydration, and hyponatremia) has remained stable since the start of the episode, though slightly higher than during the reference period.

• SOS Médecins staffing levels were very low. Nevertheless, heat-related activity began to increase as early as the beginning of June.