Key Points

Extreme heat, heat waves

• Since June 1 in Auvergne-Rhône-Alpes, there have already been three heat waves:

  • A first heat wave affected the departments of Isère and Rhône from June 20 (S25) to June 26, 2025 (S26).

  • A second heat wave affected all departments in the region from June 28 (S26) to July 5, 2025 (S27).

  • A third heat wave affected the entire region from August 8 (S32) to August 17 (S33), and four departments (Ardèche, Drôme, Isère, and Rhône) were placed under a red alert from August 12 to August 14 (S33). During this episode, 85 SOS Médecins calls were recorded for the iCanicule indicator, and there were 338 emergency room visits, 193 (57%) of which resulted in hospitalization. The age group most affected was those aged 75 and older.

Hepatitis A

• A resurgence of hepatitis A is being observed across Europe.

• In our region, the increase in cases is mainly observed in the Lyon metropolitan area. In this context, the Auvergne-Rhône-Alpes Regional Health Agency (ARS) is reminding the public of the essential preventive measures to limit the spread of this viral infection.

Chikungunya, Dengue, and Zika

• Two outbreaks of locally transmitted chikungunya were reported in the region in August:

  • Local cases of chikungunya in Eybens (Isère)

  • A locally transmitted case of chikungunya in St Ours (Savoie)