Key Points

• A widespread heat wave has been affecting mainland France since July 4. The entire population of mainland France has been under an orange or red heat wave alert. Between July 10 and 15, 37 departments were placed under a red heat wave alert, representing 39% of the mainland population.
• The number of emergency room visits across all age groups for the iCanicule indicator (hyperthermia/heatstroke, dehydration, and hyponatremia) began to rise on July 5, peaking at 587 visits on July 10. Since July 17, the number of emergency room visits related to iCanicule has been declining but remains at levels higher than those observed before the June heatwave.
• Hospitalizations resulting from these visits increased between July 6 and 10 and fluctuated between 250 and 350 daily hospitalizations through July 16.
• The number of SOS Médecins calls for the iCanicule indicator increased between July 6 and 13 (peaking at 236 calls). Since then, the number of calls has been declining but remains at levels higher than those observed before the June heat wave.
• All age groups are affected by these emergency care visits for the iCanicule indicator. More than half of the emergency room visits involved people over the age of 75, and nearly two-thirds of SOS Médecins calls involved people under the age of 45.
• 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, the impacts on morbidity do not allow us to predict mortality.