'Extreme heat reduction urgently needed to prevent unnecessary deaths'

Immediate and urgent globally coordinated efforts to mitigate climate change and increase resilience to extreme heat to limit additional warming can help save lives, say researchers.

Extreme heat is an increasingly common occurrence worldwide, with heat-related deaths and illnesses also expected to rise.

Reducing the health impacts of extreme heat is an urgent priority and should include immediate changes to infrastructure, urban environment, and individual behaviour to prevent heat-related deaths, said researchers in a new two-paper Series on Heat and Health, published in The Lancet.

"Two strategic approaches are needed to combat extreme heat. One is climate change mitigation to reduce carbon emissions and alter the further warming of the planet. The other is identifying timely and effective prevention and response measures, particularly for low-resource settings," said Kristie Ebi, Professor at the University of Washington, US.

"Failure to reduce greenhouse gas emissions and to develop and deploy evidence-based heat action plans will mean a very different future awaits many people and communities around the world," she added.

According to a new Global Burden of Disease modelling study, also published in The Lancet, more than 356,000 deaths in 2019 were related to heat and that number is expected to grow as temperatures rise worldwide. However, many heat-related deaths are preventable by mitigating climate change and reducing exposure to extreme heat, the researchers said.

When exposed to extreme heat stress, the body's ability to regulate its internal temperature can be overwhelmed, leading to heat stroke. In addition, physiological thermoregulatory responses that are engaged to protect body temperature induce other types of physiological strain and can lead to cardiorespiratory events.

Effects from extreme heat are also associated with increased hospitalisations and emergency room visits, increased deaths from cardiorespiratory and other diseases, mental health issues, adverse pregnancy and birth outcomes, and increased healthcare costs.

To counter these health effects, the researchers highlighted accessible and effective cooling strategies at the individual, building, and urban and landscape level.