Key Points

• A heat wave hit France at the end of week 25/2025. Météo France issued an orange “heat wave” alert for the five departments of the Pays de la Loire region, effective from 12:00 PM on June 20, 2025, until the evening of June 21.

• A regional analysis of emergency care utilization shows a slight increase in the iCanicule composite health indicator (including hyperthermia, dehydration, and hyponatremia) during week 25 of 2025, concentrated on June 20 and 21.

• Analysis at the Loire-Atlantique level of calls to SOS Médecins (44) indicates a slight increase in the iCanicule composite health indicator (including heatstroke and dehydration) during week 25/2025, concentrated in the period from June 19 to 22.

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