The number of deaths from all causes attributable to heat reached nearly 1,500 during the four heat waves and more than 5,000 over the entire summer monitoring period. Between June 1 and September 15, nearly 20,000 heat-related visits to emergency departments were recorded. These figures highlight the impact of extreme heat during heat waves but also during hot periods throughout the summer. These findings confirm the need for prevention measures across the country and a strengthened climate change adaptation strategy to reduce the impact of heat on the health of the French population.

Twice as many emergency care visits during heat waves

Emergency care visits linked to the iCanicule indicator (including hyperthermia/heatstroke, dehydration, and hyponatremia) were observed throughout the summer and tend to increase rapidly and significantly as temperatures rise. Thus, nearly 20,000 emergency care visits were recorded during the summer. During heat waves, the number of emergency room visits for the iCanicule indicator increased by a factor of 2.1, and the number of SOS Médecins consultations increased by a factor of 3 compared to periods outside of summer heat waves. During the summer, 10,600 hospitalizations following an emergency room visit for the iCanicule indicator were recorded.

While the entire population is affected by the impact of heat, it is noted that more than half of the emergency room visits for iCanicule involved people aged 75 and older.

1,500 heat-related deaths during the four heatwave episodes and more than 5,000 deaths throughout the entire monitoring period

During heatwave episodes, the number of all-cause deaths attributable to heat totaled more than 1,500, representing over 10% of all-cause mortality observed. Over the entire summer monitoring period (June 1 to September 15), the number of all-cause deaths attributable to heat totaled more than 5,000, representing more than 3% of all-cause mortality observed. All age groups are affected, with 75% of these deaths occurring among people aged 75 and older.

In addition, eleven fatal workplace accidents potentially linked to heat were reported by the General Directorate of Labor. These fatal workplace accidents occurred throughout the summer (even outside periods of orange or red heatwave alerts) and primarily involved men aged 19 to 70. Nearly half of these fatal workplace accidents occurred in the context of construction and related work.

A strengthened prevention program targeting vulnerable populations

The 2023 prevention program consists of two phases:

• Starting in May, available prevention tools (posters, informational leaflets for distribution) are promoted among healthcare professionals and regional stakeholders;

• during heat waves, digital content is released as soon as a department is affected (10 times this summer, with 58.7 million screen views). When the heat wave affects a large part of the country, a TV spot and three radio spots (in English and French) are broadcast exclusively through media buyouts.

This year, Santé publique France also launched a new initiative to help people adapt to extreme heat, with the goal of instilling in the population healthy behaviors related to heat in daily life—not just during heat waves. This initiative will be expanded in 2024.