During the three heatwave periods, the estimated national excess mortality from all causes combined was 2,816 deaths, equating to a relative excess mortality of +16.7%. These episodes occurred in a unique context, both in terms of the health situation—with the resurgence of COVID-19—and the climate situation. This review emphasizes the importance of anticipating the impacts of hot weather in advance of heatwaves and, in this regard, supports the need to strengthen the strategy for mitigating and adapting to climate change across the entire country. Regional bulletins are also available.

Use of emergency care due to hot weather throughout the summer

Between June 1 and September 15, 2022, over 20,000 instances of healthcare use (emergency department visits, consultations with SOS Médecins) were recorded for the heatwave indicator ‘iCanicule,’ covering hyperthermia, dehydration, and hyponatremia.

More than 17,000 of these cases were visits to emergency departments, including 10,000 hospitalizations. Half (51%) of these emergency department visits and 29% of consultations within the SOS Médecins network of physicians involved people aged 75 and older.

This represents double the number of emergency department visits and triple the number of SOS Médecins consultations observed during periods without a heatwave.

It is not possible to predict the impact of heat on mortality based on these uses of emergency care.

2,816 excess deaths during heatwave periods

The impact of heatwaves on mortality is estimated by comparing the number of deaths observed during the episodes to the number of deaths that would have occurred in the absence of a heatwave. The estimates calculated reflect the excess deaths recorded during heatwaves in the affected regions, but these cannot be attributed solely to heat.

In 2022, during the three heatwave periods² and in the affected regions, there were an estimated 2,816 excess deaths, or a relative excess mortality of +16.7%.

Four regions cumulatively account for nearly two-thirds of the national excess: Auvergne-Rhône-Alpes (+473 deaths), Nouvelle-Aquitaine (+436 deaths), Occitanie (+509 deaths), and Provence-Alpes-Côte d’Azur (+316 deaths). These were the regions most affected by heatwaves, which struck with great intensity in the southwest and at repeated, extended intervals in the southeast.

The highest excess mortality was observed during the second heatwave (+22.7%) in July. People aged 75 and older were the most affected, with 2,272 excess deaths, meaning that 1 in 6 deaths in this age group was excess.

Relative excess mortality was higher in regions where the French meteorological service issued red heatwave warnings (+19.9%) than in other regions.

During the three heatwave periods^³ and in the same regions, 894 deaths due to COVID-19 were recorded in hospitals and in residential care facilities^⁴. People aged 75 and older accounted for three-quarters of these deaths. Deaths due to COVID-19 cannot be subtracted from the figures for excess mortality during the heatwaves: COVID-19 may have increased susceptibility to heat in some people, while exposure to heat may have worsened the condition of certain COVID-19 patients.

Across the entire summer 2022 monitoring period (from June 1 to September 15), there were an estimated 10,420 excess deaths from all causes (+6.1%) in metropolitan France. Part of the summer excess mortality was likely caused by the population’s exposure to high temperatures that did not reach the heatwave alert threshold. Santé Publique France is currently working on an estimate for the attributable proportion.
Also during the monitoring period, seven reports of potentially heat-related fatal workplace accidents were submitted by the Direction générale du travail [General Directorate for Labor] to Santé publique France. These involved men aged between 39 and 54, with a median age of 44 years. The fatal accidents mainly occurred during outdoor work activities, including three deaths in the construction sector.

Escalation of climate change

Summer 2022 followed the trend observed over the past few years, whereby the escalating exposure to heatwaves in summer translates into a rise in the associated health impacts. Other weather phenomena occurred in summer 2022 alongside the heatwaves: intense and long-lasting drought across the entire country and forest fires affecting some regions for the first time. These kinds of phenomena may increase with climate change.

Since 2015, prolonged heatwaves that are atypical in terms of intensity or the time and place of occurrence have resulted in excess mortality every time.

In the context of climate change, these findings underscore the need to strengthen strategies for mitigating and adapting to climate change, both nationally and regionally.

Preventing the health effects of heatwaves

The national prevention program, which aims to encourage the public to take steps to protect their health during very hot weather, included a pilot text-messaging campaign this year.

The scheme is based on two components. The “non-heatwave” component is activated prior to the start of the monitoring period, informing local and regional communities and authorities (regional health agencies, local administrative authorities, support networks for the elderly and home caregivers, childcare networks, disability networks, health workers’ associations, etc.) that resources are available.

The “heatwave” component is activated only during episodes of extreme heat and consists of announcements broadcast on the radio or social media, plus a TV spot and two radio spots (in English and French), broadcast only if channels are allocated for this purpose.

For the first time, a large-scale text messaging campaign was tested during periods of yellow and orange heatwave warnings. The campaign targeted populations vulnerable to heat: adults aged 65 and older, pregnant women, and parents of young children. In total, over the course of the three heatwaves, more than 4 million text messages were sent out.

In addition, the heatwave information helpline, which offers advice on protecting oneself and others, particularly those most vulnerable to heat, was active for a total of 26 days this year between June 16 and August 13.

The current prevention program is being evaluated to determine the extent of its coverage and its effectiveness, and to identify areas where prevention efforts can be improved as part of a climate change adaptation strategy.