Key Points

• A heat wave affected France during week 27 of 2025. Météo France issued an orange “heat wave” alert for the five departments of the Pays de la Loire region, effective from June 29, 2025, through the evening of July 2.

• A regional analysis of emergency care utilization shows a slight increase in the iCanicule composite health indicator (including hyperthermia, dehydration, and hyponatremia) during the period from June 29 to July 5.

• Analysis at the Loire-Atlantique level of calls to SOS Médecins (44) indicates a slight increase in the composite health indicator iCanicule (including heatstroke and dehydration) over the period from June 29 to July 5.

• This trend falls within the expected fluctuations for the current weather conditions and is observable across the region as a whole.