ALTHOUGH the public accepts that climate change is a major issue that must be addressed in the interest of the world's environment and future economy, many health professionals have asked: what has climate change to do with health? Hopefully this question was put to rest when the World Health Organisation selected "protecting health from climate change" as the theme for World Health Day last April 7. WHO recognises that climate change is posing an ever-growing threat to global public health and that "wherever you live, climate change threatens your health".

Nevertheless, the implications are difficult to grasp for the consequences are multiple and disparate, some obvious, others complex. Climate change will bring to Australia an increased burden of heat stress, injury from fire and storm, social disruption and mental illness; in the developing world it will bring famine, water shortage and dislocation of populations with calls to Australia to assist resettlement. The coming disruption of ecological services that provide humanity's life-support system is likely to have far-reaching health impacts on food and water resources and on the spread of infective disease.

It is difficult for the health professions to garner interest in the issue because it is an intergenerational problem, one in which we are seeking to protect the health of future generations. The quest for the government's attention has to compete with the day-to-day challenges of health service delivery and resources, and there is an underlying difficult political issue created by the lobbying power of those with vested interests. In some respects the performance of the tobacco lobby has been replayed in denial and subterfuge by some in the fossil fuel industries.

However, there is increasing recognition that the health professions need to guide our governments on the health impacts of climate change and to advise how these might change clinical practice. A start was made this year when Doctors for the Environment Australia presented its report, Climate Change Health Check 2020 (http://www.dea.org.au/). There are health implications in pending government decisions on infrastructure deployment and the introduction of an emissions trading scheme (ETS). The science is unequivocal that emissions must be curtailed urgently to reduce the possibility of dangerous climate change. This urgency demands an ETS commencing in 2010 with a target of 20 per cent, or preferably 25 per cent, by 2020. Success is likely if renewable energy sources are dispensed aggressively.

Renewable energy has health bonuses. It is non-polluting and reduces reliance on fossil fuels, which emit carbon dioxide and many other pollutants responsible for much cardio-respiratory disease. Renewable energy is decreasing in cost and creates many more jobs per equivalent amount of power than does fossil fuel. It can be used as a distributed energy source, a positive for social welfare and health as it distributes employment opportunities to regional and rural centres where the burden of stress, depression and suicide is increasingly prevalent. It is important that renewable energy is at the forefront of our federal government's infrastructure proposals. Investment in renewable energy installation should also be promoted by a generous national "feed-in" tariff which would offer additional support to regional and rural communities by providing a steady, though small, financial return.

Energy saving will also contribute to achieving a 25 per cent reduction in emissions by 2020, and here the health professions can play a significant role. Many report that energy wastage in hospitals is prodigious, yet officially we are told it is being successfully addressed in public hospitals. The overall situation in private hospitals is unclear. In our clinics and homes we can effect energy saving and offer advice to our patients by providing educational material in our practices. This emphasises climate change as a health issue that will affect everyone.

Some doctors ask if our profession should involve itself in issues that are seen to be in the national political domain. When there are health implications in government policy we must all be involved. There is no philosophical difference between our need to advocate measures in climate change and our need to define and prescribe lifestyle changes for the control of obesity; indeed there is a significant coincidence between measures necessary to avoid obesity and those which can reduce greenhouse emissions.

We must act now, for in the words of the French philosopher, Paul Valery, "the future, like everything else, is not what it used to be".

(Por David Shearman and Michael Kidd, The Australian, 06/12/2008)