Key Points

In mainland France, June and July 2019 were marked by two widespread and intense heat waves. During these two heat waves, for the first time since the implementation of the National Heat Wave Plan (PNC), mainland departments were placed under a red alert due to exceptionally high daytime temperatures.

In Provence-Alpes-Côte d’Azur, these two heatwave episodes resulted in alert thresholds being exceeded across the entire region during the first episode in June and in two departments (Alpes-de-Haute-Provence and Hautes-Alpes) during the second episode in late July. Two departments (Bouches-du-Rhône and Vaucluse) were placed under a red heat wave alert (for two consecutive days) for the first time during the first episode. A significant impact on health was observed during these periods:

• During the periods when alert thresholds were exceeded and for the affected departments in the region, 102 [59–138] excess deaths were estimated, representing a relative excess mortality rate of +8.5%. The first heatwave episode, which was more intense, accounted for nearly 93 deaths on its own. People aged 65 to 74 were the most affected (41 deaths) during both episodes.

• Heat-related conditions (defined by the iCanicule indicator, which includes hyperthermia, dehydration, and hyponatremia) accounted for 1.7% of emergency room visits and 2.5% of SOS Médecins calls during the first episode. During the second episode, this activity was lower, accounting for 0.8% of emergency room visits and 0.9% of SOS Médecins calls. The hospitalization rate following an emergency room visit during these two episodes was 52.9% and 62.0%, respectively. While the impact was greater among those aged 75 and older, all age groups were affected.

While the health impact of the heat increased significantly with rising temperatures, particularly during the first heatwave, it was not limited to these periods alone, as two-thirds of emergency room visits and half of the SOS Médecins calls observed in the Provence-Alpes-Côte d’Azur region occurred outside of these two heatwaves. This highlights the importance of disseminating prevention messages throughout the summer season.