Key Points

• A widespread heat wave affected mainland France between July 4 and 22. During this period, the entire population of mainland France was subject to at least one day of an orange heat wave alert. Between July 10 and 15, 37 departments were placed under a red heat wave alert, covering 39% of the population of mainland France. The monitoring data presented in this bulletin covers the period from July 4 to 27.
• The number of emergency room visits across all age groups for the iCanicule indicator (hyperthermia/heatstroke, dehydration, and hyponatremia) increased starting on July 5, peaking at 587 visits on July 10. Between July 17 and 24, the iCanicule indicator fluctuated between 190 and 250 visits per day.
• Hospitalizations resulting from these visits increased between July 6 and 10 and ranged between 250 and 350 per day through July 16. The number of daily hospitalizations fluctuated between 250 and 350 through July 16, then between 110 and 160 from July 17 through July 25.
• The number of SOS Médecins calls for the iCanicule indicator increased between July 6 and July 13. A peak of 236 calls was observed on July 13, after which this indicator gradually decreased to between 30 and 53 daily calls between July 20 and July 26.
• All age groups were affected by these emergency care visits for the iCanicule indicator, particularly those aged 75 and older.
• The trends observed in healthcare utilization are consistent with temperature trends. These impacts underscore the importance of implementing prevention and adaptation measures for the entire population, based on weather forecasts, without waiting to observe actual impacts. As a reminder, impacts on morbidity do not allow us to predict mortality.