WHO says climate inaction costs lives, strains global healthcare workforce

The World Health Organization has declared that the climate crisis is the greatest threat to global health in the 21st century, with rising temperatures driving direct and immediate impacts for Australians and straining the nation’s healthcare system.

The 2025 Lancet Countdown on Health and Climate Change report, produced in collaboration with the World Health Organization (WHO), reveals that continued reliance on fossil fuels paired with an insufficient adaptation to a warming world are severely affecting human health.

For Australia’s healthcare workforce, this means facing increased patient demand, compromised infrastructure, and heightened burnout.

“The climate crisis is a health crisis. Every fraction of a degree of warming costs lives and livelihoods,” WHO assistant director-general for health promotion and disease prevention and care Dr Jeremy Farrar said.

“However, climate action is also the greatest health opportunity of our time. Cleaner air, healthier diets, and resilient health systems can save millions of lives now and protect current and future generations.”

Impacts of a warming planet

The 2025 report identifies 12 of 20 key indicators tracking health threats at record levels, showing how climate inaction costs lives, strains health systems, and affects economies globally.

In 2024, Australians experienced an average of 8.1 heatwave days, with 5.4 (67 per cent) directly linked to climate change. This increase in extreme heat affects vulnerable populations; premature births, kidney disease, heart attacks and deaths all increase during heat wave.

Visiting fellow at the University of Technology Sydney Milton Speer said it is “indisputable” that both minimum and maximum temperatures have increased significantly since the 1990s.

“In Australia heat-related deaths have increased because during the warm season and particularly summer, maximum temperatures are increasingly appearing in the top 90 per cent since the 1990s compared to decades prior to the 1990s,” Dr Speer said.

“Higher minimum temperatures also affect health by making it more difficult to sleep in economically deprived areas.”

Annual heat-related deaths in Australia have risen by 83 per cent from the 1990s to 2012–2021, reaching an average of 980 deaths per year. Furthermore, the Lancet report shows that Australians now endure 56 per cent more heatwave days annually compared with 1986–2005.

Along with rising temperatures, bushfire smoke, air pollution and other extreme weather events are contributing to an increase in climate-related health problems, with 43 per cent of the country experiencing at least one month of extreme drought in 2024.

“Increasing droughts from climate change-induced higher temperatures and altered rainfall patterns due to atmospheric circulation changes threaten food productivity, compromise water security and increase the risk of waterborne infectious diseases,” Dr Speer said.

“The combination of increased heat, increased moisture availability from warming oceans together with changes in the atmospheric circulation have led to devastating extreme rainfall events worldwide, and as the report states, the rate of increase in all types of these extreme events has been alarming in the last five years or so.”

Strain on the healthcare system

In September, the federal government released its first National Climate Risk Assessment, which laid bare the climate-related health risks Australians face now, and into the future.

The report showed heatwave deaths are expected to quadruple in Sydney and Darwin at +3℃ of global warming.

Doctors for the Environment Australia (DEA) executive director Dr Kate Wylie warns of more deaths and illness, greater spread of infectious diseases and increased mental health challenges.

“We are right now witnessing the effects of climate change on the health of Australians – increased emergency department presentations and hospitalisations due to heat, the mental health impacts of extreme events like floods and fire, and the emergence of infectious diseases like Japanese encephalitis virus in previously unaffected areas of Australia,” Dr Wylie said.

“Healthcare services are also vulnerable to a range of risks, including an increase in patient demand and threats to infrastructure and workforce.”

Backtracking on net zero

Against this backdrop, the Coalition announced in November its decision to abandon Australia’s commitment to net zero by 2050. During its time in government in 2016, it was the party that committed the country to the Paris Agreement – an international treaty that aims to limit global warming to below 2℃, compared to pre-industrial levels – and set Australia’s net zero target in 2021.

The Liberals have still agreed to reducing emissions year-on-year within five year blocks, tying those reductions to comparable countries, as well as staying in the Paris Agreement.

DEA has strongly condemned these attempts to reduce measures towards a safe climate, urging “all parliamentarians to put health before ideology.”

“It would be reckless for our political leaders to ignore the scientific and medical evidence that clearly states climate change is a public health emergency,” Dr Wylie said.

“Dropping net zero aimed at addressing rising emissions, which are the cause of climate change, threatens the foundations of good health, with serious consequences for our families and communities.

“The health impacts of climate change are an escalating threat that our leaders must be prepared to face and address.”

Calls for action

In light of these political developments, the Australian Nursing and Midwifery Federation (ANMF) has partnered with The Lancet Countdown to launch a national policy report calling on the Australian government to place health at the centre of climate change policy.

“As Australia’s largest health workforce, nurses and midwives see first-hand the growing impact of extreme heat, poor air quality and displacement caused by climate disasters. That’s why we’re calling on the Government to adopt these recommendations to better protect people across the community,” ANMF federal secretary Annie Butler said.

The policy report recommends three key priority actions:

1. Adapt a national clean air framework for health: With over 3,400 deaths in Australia attributed to fine particulate matter air pollution in 2022, a legally binding framework with continuous monitoring and cross-sector accountability is crucial.
2. Urgent investment to implement a national health and climate strategy: While a roadmap exists, dedicated government funding is needed to strengthen health system resilience, particularly as older Australians face significantly more heatwave days.
3. Redirect fossil fuel subsidies toward health and climate resilience: Redirecting Australia’s US$10.8 billion in fossil fuel subsidies could unlock significant economic and social benefits for the country.

The Lancet report also highlights positive developments, with the health sector showing impressive climate leadership, dropping health-related greenhouse gas emissions by 16 per cent globally between 2021 and 2022. Furthermore, almost two-thirds of medical students worldwide received education in climate and health in 2024, building the capacity for future progress.

The Lancet Countdown director Marina Romanello said there is hope among the statistics, highlighting that “climate action is a lifeline for health.”

“Translating evidence into action is our chance to protect lives and build a healthier, more prosperous future,” Dr Romanello said.

“We already have the solutions at hand to avoid a climate catastrophe – and communities and local governments around the world are proving that progress is possible.

“From clean energy growth to city adaptation, action is underway and delivering real health benefits – but we must keep up the momentum. Rapidly phasing out fossil fuels remains the most powerful lever to slow climate change and protect lives.

“At the same time, shifting to healthier, climate-friendly diets and more sustainable agricultural systems would massively cut pollution, greenhouse gases and deforestation, potentially saving over 10 million lives a year.”