GENEVA — Heat waves that swept Europe and parts of North America in 2026 have contributed to a sharp rise in deaths, with health authorities warning that the toll from extreme temperatures is still being assessed as another summer of unusually intense heat strains communities and health systems.
The World Health Organization said on July 16 that data from five European countries already showed nearly 10,000 excess deaths this summer, while stressing that the final toll remained under assessment. The agency said extreme heat was placing growing pressure on health and social-care services across the region.
Europe experienced an intense heat wave in June, with western Europe recording its hottest June on record, according to the Copernicus Climate Change Service. Europe as a whole had its second-warmest June, while persistent dry conditions and extreme temperatures contributed to wildfire risks across the continent.
National mortality data have also pointed to a significant increase. France's public health agency reported an increase of nearly 30% in all-cause deaths during the week of June 22-28 compared with the previous week, although it cautioned that the figures were preliminary and incomplete and said a dedicated assessment of excess mortality from the heat wave would follow.
WHO Regional Director for Europe Hans Henri P. Kluge said on June 30 that Spain's mortality monitoring system had estimated more than 300 heat-associated excess deaths in a few days, while Italy reported five deaths in 24 hours. WHO has said Europe is warming at about twice the global average rate, increasing the frequency and intensity of extreme heat events.
The impact has extended beyond Europe. North America has also faced extreme heat and wildfire conditions, including widespread fires in Canada that have affected air quality across parts of the country and the northeastern United States. However, comprehensive continent-wide mortality figures for the 2026 heat season were not available from the sources reviewed, making direct comparisons with Europe's preliminary excess-death estimates premature.
WHO said heat can worsen cardiovascular disease, diabetes, asthma and other underlying conditions, with older people particularly vulnerable. The agency estimates that heat-related mortality among people aged over 65 rose by about 85% between 2000-04 and 2017-21.
Authorities across Europe have continued issuing heat-health warnings and urging residents to limit exposure during the hottest periods. WHO said on July 7 that further heat waves were developing, with Portugal and southern Spain forecast to reach 43°C, while France and the Benelux region prepared for another surge.
