Preparing for a future of extreme heat

Residents of Asia are eagerly awaiting the end of the extreme heat season, which is now drawing to a close. In my country, the Philippines, the first typhoon of the year came at the end of May, which helped bring down temperatures that reached almost 50° Celsius. In previous months, record-breaking heat has led to school closures, an increase in emergency room visits, a drop in productivity and a return to working from home.

Although the impact of extreme heat on public health and the economy is difficult to measure, what is striking is the speed with which it is all forgotten. This is similar to the panic/forget cycle that usually occurs after a pandemic: societies forget the lessons of past health crises and find themselves unprepared when the next one begins.

We need to improve pandemic preparedness, just as we need to mitigate the health risks posed by life-threatening, elevated temperatures. As climate change accelerates, extreme heat waves are expected to become more intense and more frequent, especially in Asia. In order to survive in this "new normal", it will not be enough to follow inappropriate medical advice, such as drinking more water and staying in air-conditioned spaces, as if the majority of the world's population had access to air-conditioning and drinking water.

No, the authorities need to take a more proactive approach and accelerate efforts to build resilience to the heat. By the time the next record heat wave hits, all countries should have a national plan to address the problem, along with adaptation measures for local communities. In fact, every aspect of policy making should be viewed through the lens of resilience. In addition to the health sector, the main priorities should be housing, transport and water supply - which corresponds to the Sustainable Development Goals.

It should start with housing. Many of the most vulnerable people in Asia live in poorly ventilated apartments or overcrowded slums. An estimated 1,6 billion people worldwide suffer from inadequate housing conditions. Given that such studies usually do not take ventilation into account, this figure could be even higher.

There are more realistic ways to adapt to climate change than telling poor people to live in air-conditioned spaces. Air conditioners are not only expensive, but also consume huge amounts of electricity. Researchers estimate that air conditioning accounts for 3,9% of global greenhouse gas emissions. Instead of burning more fossil fuels to meet the increased demand for electricity, authorities need to rethink approaches to urban development to protect both the planet and public health. For example, a number of countries in Asia, including Indonesia and Singapore, have begun using inexpensive "cool roof" paint to help reduce indoor temperatures in non-air-conditioned buildings.

Transport is another sector sensitive to heat. Whether it's traveling in the heat on crowded buses or waiting for a train on a platform, travelers in low- and middle-income countries are often exposed to extreme temperatures. Investing in sustainable transportation systems that provide comfort during heat waves is critical to achieving vital climate and health goals.

To build resilience to heat, governments must also address the global water crisis. Although staying hydrated is essential to protect against extreme heat, nearly a third of the world's population does not have access to clean drinking water. Single-use plastic water bottles are not the answer. Like air conditioning, it's an expensive, carbon-guzzling and polluting approach.

Heatwave preparedness programs should focus on the most vulnerable groups, including farmers, fishermen, construction and factory workers, the elderly and the sick. There are also prisoners, detained migrants and the mentally ill, who are often confined in extremely hot areas with many people.

Like storm or pandemic response protocols, extreme heat preparedness should be part of public health policy. To this end, disease surveillance systems should be updated to include heat-related diseases. This should be done before the start of another period of record heat. In addition, it is important to maintain an adequate supply of medical supplies, ranging from basic supplies (eg, intravenous fluids) to cooling vests.

Information about the potential consequences of extreme heat should be included in education and training programs for emergency physicians, community health workers, and primary care providers. They are usually the first to contact low-income patients. Unfortunately, clinical treatment of heat-related illnesses (eg heatstroke) was only mentioned in passing when I was a medical student.

Finally, scientists must focus not only on the epidemiology of heat, but also on the effectiveness of our regulations and measures. For example, the National University of Singapore opened a special center for the study of heat tolerance in 2023. (...)

With global temperatures rising at an alarming rate, we have no choice but to adapt to a warming world. At the same time, accelerating decarbonisation would allow us to reduce the frequency and intensity of extreme heat waves. By demanding that governments and corporations stop burning fossil fuels, we can build true resilience to the heat and improve the health of the planet.

The author is an associate professor of global and planetary health at the Duke-NUS School of Medicine in Singapore

Copyright: Project Syndicate, 2024. (translation: NR)