Heat linked to 600 premature deaths in Switzerland this summer
Tuesday 22nd September 2026 on 18:01 in
Switzerland
About 600 more people than usual died in Switzerland between June and September during the country’s hottest summer since records began in 1864, according to SRF.
The first heatwave, which struck in late June, had the greatest impact. Martina Ragettli, an epidemiologist at the Swiss Tropical and Public Health Institute, said people are not yet adapted to high temperatures at the start of summer, making the first heatwave often the most dangerous.
A second, longer heatwave arrived in early August after a short break in July. People had largely returned to their normal routines and had fewer opportunities to protect themselves from the heat, Ragettli said.
People over 65 were affected most often, but the number of deaths among those under 65 also rose noticeably during the second heatwave. Ragettli said this may have been because people had returned to workplaces such as construction sites, shops and care facilities, where they could be less able to escape the heat than during holidays. The duration and intensity of the heatwaves may also have played a role.
These explanations remain assumptions. The people concerned were not officially recorded as having died from heat. Their death certificates listed causes such as heart attacks or circulatory failure, with heat considered a trigger rather than the diagnosis.
Weekly monitoring by the Swiss Federal Statistical Office shows that an unusual number of people died, but not why. No other known event explains the increase in mortality, however.
A more precise assessment using temperature data is being conducted by the Swiss Tropical and Public Health Institute. The analysis is due to be published in spring 2027.
Heat-related mortality reached its previous peak in 2003 and has generally declined since then, suggesting that measures such as early-warning systems are having an effect. However, only eight of Switzerland’s 26 cantons have a complete heat action plan. The cantons are responsible for such measures rather than the federal government, and Environment Minister Albert Rösti intends to keep it that way for now.
The figures show that extreme heat is no longer only a risk for older people. With climate change, such hot summers are expected to become more frequent rather than less common.