Seniors died in stifling apartments. Emergency calls were left on hold. Doctors treated an onslaught of people sick from heat, sometimes in wards without air‑conditioning. These are scenes that played out in Belgium, one of the world’s wealthiest nations, on a recent summer weekend. They are also a warning to Europe. Europe is the fastest‑warming continent, yet large parts remain ill prepared. As heat waves scorch its nations this summer, they are killing thousands in countries with strong health systems.

In just one week in late June, there were around 16,000 excess deaths, or more people who died than usual, in Europe. Belgium, France and Germany were the worst affected, based on data collected by the European Mortality Monitoring Network. Belgium, known for cold and damp, not searing heat, had the highest excess deaths in Europe, making it a case study into what went wrong. In Wallonia, the region that makes up the country’s south, the death rate was 77 % higher than what would be expected between mid‑June and early July.

Some hospitals were overrun, with gurneys and patients lining the hallways and medical staff working without breaks in the unrelenting heat. “Each crisis is becoming increasingly severe,” said Yves Coppieters, the health minister for Wallonia. “That’s what we’re failing to anticipate.” Climate change means that the issue is most likely here to stay. “The future that we’re seeing, it could be much worse,” said Joan Ballester Claramunt, a research professor at the Barcelona Institute for Global Health.

Emergency systems buckled under pressure, structural challenges left the most vulnerable to suffer, and Belgium’s cold‑country mentality about cooling made the crisis worse. Low‑income seniors and those living alone were hit hardest. “The mentality on air‑conditioning has to change,” echoed calls for rapid lessons and better preparation.