Europe recorded more than 10,000 excess deaths last month which have been attributed to the ongoing heatwave, Reuters reported on Sunday, citing official mortality data.

Western Europe experienced its hottest June on record, with temperatures exceeding 40°C in parts of Germany, France, and Spain. Germany recorded a new national high of 41.7°C after breaking temperature records on three consecutive days, while France logged its hottest day ever, with temperatures reaching 43.8°C.

The prolonged heatwave has fueled wildfires, disrupted transport and infrastructure, and contributed to a rise in heat-related illnesses and drowning deaths across the region.

Figures published by EuroMOMO, a mortality monitoring network backed by the European Centre for Disease Prevention and Control (ECDC) and the World Health Organization (WHO), showed that more than 9,000 of the excess deaths occurred among people aged 65 and older.

“To have this kind of excess at this time of year is unusual. It’s really high,” Lasse Vestergaard, chief physician at Denmark’s Statens Serum Institut, which hosts EuroMOMO, told Reuters.

“It is difficult to explain this high excess mortality by anything but the extreme heat,” he added.

The EuroMOMO data are based on national mortality statistics from 27 European countries for the week of June 22-28, when the heatwave peaked across much of Western Europe. Researchers told Reuters there were no other known major factors, such as Covid-19 outbreaks, that could explain the spike to 10,650 excess deaths.

Extreme heat has become Europe’s deadliest weather-related hazard. Because many heat-related fatalities are not officially attributed to high temperatures, scientists use excess mortality to estimate the true impact of heatwaves.

Around 2,700 excess deaths were separately reported in England and Wales during May and June, according to estimates by Imperial College London, the Met Office, and the London School of Hygiene & Tropical Medicine, as cited by Sky News.

France, Belgium, and the Netherlands recorded 3,700 excess deaths last month, Reuters reported.

Extreme heat can kill by causing heat stroke or exacerbating cardiovascular and respiratory diseases, with older people among the most vulnerable.

Henri Kluge, the World Health Organization’s regional director for Europe, warned last week that European countries must prepare for “more deadly weeks,” as another heatwave was already forming over the Atlantic.