More than 2,700 people died from heat-related causes during May and June's record hot spells, according to a new analysis by researchers from Imperial College London, the Met Office, and the London School of Hygiene and Tropical Medicine (LSHTM). The study estimated 2,700 excess deaths in England and Wales over two heatwaves, with climate change driving up the toll significantly. Over 42% of deaths were attributed to extra heat caused by human activity, primarily burning fossil fuels.
Breakdown of deaths by heatwave
The analysis found that about 550 people died from heat-related causes during the nine-day May heatwave, and approximately 2,200 died during the 11-day June heatwave in England and Wales. Of these, 59% of May deaths (327 people) and 38% of June deaths (825 people) were attributable to climate change-driven heat.
Health risks and expert warnings
High temperatures are associated with heat exhaustion, heat stroke, cardiovascular stress, and worsening chronic conditions like heart disease, lung conditions, and diabetes. They also exacerbate mental health issues, violence, and drowning risks. Dr Mark McCarthy of the Met Office described the heatwaves as 'exceptional,' noting the June event's humidity and early timing. Dr Clair Barnes from Imperial College London urged authorities to treat extreme heat like winter flu, adding: 'People need to be aware that we are now seeing dangerous climate-change fuelled heat that is claiming lives, disrupting schools and hospitals and shutting down transport and infrastructure. It's time we woke up to the fact that we now live in a country with dangerously hot summers.'
Infrastructure and preparedness gaps
The Climate Change Committee warned the UK is unprepared for extreme heat, predicting 92% of homes could overheat by mid-century, and called for workplace temperature limits and air conditioning in hospitals, care homes, and schools. London Ambulance Service reported its busiest week ever during the June heatwave, with a record number of life-threatening emergencies. Deputy chief paramedic Alison Blakely said: 'As temperatures remain high, we would urge Londoners to take the heat seriously, stay hydrated and avoid strenuous activity such as running during the hottest parts of the day, as it puts extra strain on your heart and lungs.'
