The biggest boost to public health this century could come from the same actions needed to tackle climate change, such as shutting down coal-fired power plants and designing better cities.
British medical journal The Lancet – one of the most prestigious in the world – has drawn together a team of more than 40 health experts from Europe and China to produce a major assessment of what harm climate change will cause to human health.
The review, the first The Lancet has commissioned since 2009, finds climate change represents a “potentially catastrophic” risk to human health that threatens to undo 50 years of medical gains.
But the 2015 assessment also tries to paint an optimistic picture that action to halt climate change, and to prepare for its impacts, presents a significant opportunity to improve the health of people around the world.
“Given the potential of climate change to reverse the health gains from economic development, and the health co-benefits that accrue from actions for a sustainable economy, tackling climate change could be the greatest global health opportunity of this century,” the report says.
While the exact magnitude of climate change’s hit to human health is hard to predict with precision, The Lancet’s report says it will be pervasive. Later the report says on current emissions trends there could be serious population health impacts in every region of the world within 50 years.
The report points to conservative World Health Organisation estimates that well understood climate change impacts alone could lead to an additional 250,000 deaths between 2030 and 2050.
There are a number of ways climate change is expected to harm human health.
Direct impacts
Extreme weather events such as droughts, bushfires and intense storms pose significant health risks. They are also the kind of events projected to become more frequent and intense under climate change.
For example, heatwaves have been well linked to the premature deaths of vulnerable people such as the elderly and homeless. In 2014 a heatwave that hit Melbourne was estimated to have killed 167 people. More than 2000 deaths have been attributed to a heatwave in India this year.
Indirect impacts
Climate change will also cause have other, less direct, health threats, such as shifting where diseases are found, disrupting food production and spreading air pollution.
Earlier this year the Australian Academy of Science warned that diseases in the country’s tropical north will travel south due to warming temperatures, while mosquito-borne illnesses will dramatically increase.
Stopping climate change will be good for our health
Amid all the gloom, The Lancet’s review says the health of the planet and humans can be improved at the same time.
By not burning fossil fuels improvements in air pollution will be gained and respiratory disease reduced. Encouraging more active transport, such as walking and cycling, will cut down on both transport emissions and rates of obesity, diabetes, coronary heart disease and stroke.
They say the technology to decarbonise the global economy, and gain the subsequent health benefits, is available but politics remains a barrier. The report draws parallels between climate change and other big public health issues, such as HIV and smoking, where initial denial and lobbying was overcome and global action launched.
A strong international carbon price should be established and renewable energy expanded in low and middle-income communities, the report also recommends, while the health impacts of climate change should be reported on every two years.
Australia not prepared
In the wake of The Lancet’s review, Australian Medical Association president Brian Owler told Fairfax Media the Australia health system was not prepared for climate change.
He said a centre to monitor disease spread should be considered, while medical students would have to be trained on the issues.
“We are going to see different diseases appearing in different parts of the Australian continent compared to what we have previously seen,” Dr Owler said.
Nobel laureate and immunologist Professor Peter Doherty – who will speak at the Australian launch of The Lancet’s review on Tuesday evening – said the review was important because it treated climate change as a medical problem, looking at both the causes and symptoms of the problem.
“There are co-benefits to human health, and there is a economic co-benefit,” he said.
“And if we don’t take advantage of that we are going to miss out in a big way. And at the moment we are going exactly in the wrong direction.”