Excess deaths surged as heat wave hits Europe

European countries recorded thousands of additional deaths during last month’s brutal heat wave, according to preliminary data.

Temperatures across much of the Continent soared in the middle of last month, smashing records between July 18 and 20. 

The U.K. recorded 40 degrees Celsius for the first time that week, in a heat wave scientists said was made at least 10 times more likely by climate change. Europe sank deeper into drought, wildfires ravaged thousands of hectares of forest and air pollution surged. 

The heat wave also coincided with a significant spike in the number of deaths, according to POLITICO’s analysis of data published by several national statistics offices. 

Germany, where temperatures hit 40C as far north as Hamburg, saw a particularly sharp increase, figures released this week show. 

Excluding deaths attributed to the coronavirus pandemic, the country recorded more than 3,000 excess deaths in the week of July 18 compared with the last five years. 

There’s no question extreme heat is deadly, but counting the victims is difficult. 

Excess mortality doesn’t represent an exact heat wave death toll, and experts warn that it takes detailed analysis — over months or years — to determine how many people died. 

In many EU countries, including Germany, “the problem is that unlike with [coronavirus], heat is not recorded as a factor in a person’s death,” said Stefan Muthers from the German Weather Service’s center for medical and meteorological research. 

But mortality data can give a solid idea of the impact. Muthers, co-author of a major recent study on heat-related mortality in Germany, believes a link between last month’s surges in deaths and scorching temperatures is highly likely. 

“Given the correlation with regard to time and with what was expected — that with the heat wave, mortality would increase — I’m sure that more detailed analysis will confirm that the peaks visible in this time frame are clearly related to the heat wave,” he said. 

Spain and Portugal also saw excess deaths surge in mid-July, with a peak in mortality data in the week starting July 11, when several days saw temperatures of 45C in parts of the Iberian Peninsula. 

Excluding COVID, Spain recorded more than 2,700 excess deaths than the five-year average in the week of July 11 and nearly 2,500 in the following week. Portugal registered 662 non-coronavirus excess deaths in the week of July 11 and 234 the week after. 

But unlike most countries, Spain and Portugal directly attribute some deaths to heat, meaning official death toll statistics exist. For the period of July 11-24, the Spanish monitoring system lists 1,682 heat-related deaths, while Portugal’s health chief Graça Freitas said more than 1,000 people had died between July 7-18. These numbers may still be updated.

The death of a street cleaner, who collapsed on the blistering hot pavement of Madrid, galvanized attention in Spain. But fatal heat strokes are responsible for only a small fraction of heat-related deaths, Muthens said. 

More often, heat stress and dehydration worsen pre-existing conditions — particularly respiratory and cardiovascular diseases — but also other illnesses, like Alzheimer’s. 

Increased accident risk is another factor. The scientists who found that the U.K.’s heat wave had been made 10 times more likely by climate change also highlighted more than a dozen deaths from drowning as people sought to cool down, although the British statistics office cautions that such incidents have to be investigated before an attribution can be made. 

In the Netherlands, where municipal officials had to cool down bridges with water to keep them functional during the hottest days of the heat wave, authorities recorded 559 non-coronavirus excess deaths compared with the past five years.

The national health institute RIVM spoke of a “serious increase” in mid-July. But excess mortality has been elevated for months in the Netherlands — with the statistics office admitting in June they didn’t know why — making it harder to asses the impact of the heat wave. RIVM did not respond to questions. 

Persistent excess deaths also clouded the picture across the Channel. 

According to data released by the U.K. Office of National Statistics (ONS) on Tuesday, England and Wales together registered 1,180 additional deaths unrelated to coronavirus in the week the country’s all-time heat record was broken. 

But excess mortality was similarly high or even higher throughout late spring and summer, and the weekly breakdown is further complicated by a sharp drop in data, which the ONS said was related to the long Jubilee holiday weekend.

All data is provisional and other countries, including France and Italy, will release statistics toward the end of the summer. 

Researchers are also still unsure to what degree some heat-related deaths would have simply occurred a few weeks later and how that might affect heat mortality estimates, Muthers said: “That remains an open question.” 

Still, with figures indicating several thousand deaths in a single hot week, the data serves as a stark reminder of the consequences of climate change. 

Scientists say every heat wave occurring now has been made more likely and intense by climate change, and that such extremes will occur more often and with greater intensity as global warming progresses.

“Heat waves are becoming more frequent, we see that very clearly,” said Muthers. “Including in the mortality data of recent years — there are more and more years in which significantly more people die during heat waves.” 

But much of Europe remains unprepared for what’s to come. In Germany, few municipalities have heat action plans in place. 

“That next step is up to politicians. We inform, we warn, but that alone won’t do,” said Muthers. “Linked to that we need measures to mitigate this health threat. This message, I think, is only just starting to get through.” 

Cornelius Hirsch contributed reporting.