A new study led by researchers from the RECETOX centre at Masaryk University’s Faculty of Science, in collaboration with the Institute for Global Health in Barcelona (ISGlobal Barcelona), highlights the significant risk that rising temperatures pose to human health. Extreme temperatures were associated with over 109,000 deaths in Europe in 2022 and 2023 alone, and this figure is expected to rise considerably in the years ahead. The study also found that increasing temperatures will notably impact the workload of emergency medical services (EMS).
“We created an epidemiological model incorporating daily temperatures and detailed daily data on emergency medical service calls over a ten-year period across all 76 districts of the Czech Republic and Prague,” said Tomáš Janoš, environmental epidemiologist and lead author of the study. “Based on this model, we found that the risk of emergency medical service calls is significantly higher on days with high or low temperatures. Calls are almost twice as frequent on days with high temperatures as on days with low temperatures. Overall, more than 30,000 emergency medical service calls in the Czech Republic are associated with suboptimal temperatures per year.”
Detailed, age-specific data from the Czech Institute of Health Information and Statistics (ÚZIS ČR) shows that children, adolescents and young adults are the most vulnerable population groups during hot days. For instance, the risk of an adolescent patient (aged 10–19) visiting the emergency department is up to 70% higher on the hottest days of the year than on days with optimal temperatures, and almost 50% higher than the risk of a visit by a patient of any age. Almost 1 in 10 hospital visits by a child patient is associated with high temperatures.
“In infants and young children, limited thermoregulatory ability and a higher risk of dehydration may play a role,” explained Tomáš Janoš. “As people grow older, the increased risk may be associated with behavioural factors. Children and adolescents tend to spend more time outdoors, leading to increased exposure to ambient temperatures.”
The impact of extreme temperatures on human health is a long-standing concern for RECETOX. Previous mortality research suggests that for every ten cold-related deaths, there is one heat-related death. As temperatures increase, this ratio will gradually reverse over the 21st century, meaning that any decrease in cold-related deaths will be outweighed by an increase in heat-related deaths. This will result in an overall increase in deaths.
“The impact of rising temperatures on emergency medical service calls during the 21st century remains unexplored,” concluded Janoš. “However, the current ratio is already a cause for concern, and a rapid increase in the number of heat-related emergency service calls can probably be expected this century, placing a significant burden on medical departments in terms of personnel, economics, and materials. In the future, this could potentially lead to significant delays in response times or partial unavailability of emergency medical services on the hottest days of the year.”
The full study is available on the International Epidemiological Association website.
