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Climate change and the implications on human health

18 December 2009 -- We now know that climate change aggravates health problems, most of which are concentrated in the developing world. This episode discusses the impact on human health of climate change.

Transcript of the podcast

Veronica Riemer: You're listening to the WHO podcast and my name is Veronica Riemer. In this episode we look at climate change and the implications on human health.

Over the past 10 days, delegations have assembled in Copenhagen for talks aimed at paving the way for a new global treaty on climate change. The conference offers the prospect of a robust political deal, endorsed by the world's leaders and witnessed by the world's people, setting out clear targets and a timeline for translation into law. We now know that climate change aggravates health problems, most of which are concentrated in the developing world. WHO's Director-General Dr Margaret Chan says that the impact on human health is the most significant measure of the harm done by climate change.

Dr Margaret Chan: Already, nearly one billion people live on the margins of survival. It does not take much to push them over the brink. Food insecurity, water scarcity, storms, floods, droughts, population displacements, and polluted air – all of these events have a well-documented impact on health.

Veronica Riemer: Dr Chan says that policy-makers have been slow to realize the threat of climate change to human health.

Dr Margaret Chan: I have personally attended high-level conferences on climate change where health was treated as a peripheral issue. This must change. Health concerns need to be at the centre of the debate. The impact on human health is the most significant measure of the harm done by climate change.

Veronica Riemer: Dr Diarmid Campbell-Lendrum, works on climate change and health at WHO headquarters. He talks to us about the main risks.

Dr Campbell-Lendrum: The main health risks that we see from climate change are basically worsening problems that we already have. We already have a very large burden of disease from diarrhoea – it kills about 2.2 million people every year, almost all of them children in developing countries. There are about 1.1 million deaths each year from malaria and other vector borne diseases and malnutrition is the single biggest contributor to the burden of disease and that kills about 3.5 million people every year, again mainly poor children in developing countries. All of those conditions are highly sensitive to temperature and precipitation so basically the on-going changes that we are seeing in the global climate, threaten to make those current problems even worse and even harder to control.

Veronica Riemer: Professor Andy Haines is Director of the London School of Hygiene & Tropical Medicine. He recently chaired the International Task Force on Climate Change Mitigation and Public Health which looked at the public health effects of green house gas mitigation strategies. The task force focussed on four main sectors, household energy, urban land transport, food and agriculture and electricity generation. They looked at policies that could substantially cut green house gas emissions and then assessed the impact of those policies on health.

Sir Andy Haines: In all four of those sectors there are potentially quite substantial benefits to be had to public health. In lower income countries we could get major benefits to public health in the near term by reducing indoor air pollution – responsible for 1.6 million deaths a year –and much of it comes from the burning of biomass fuels in every inefficient cook stoves. That is a major public health problem which has an impact particularly on the health of children and women.

Veronica Riemer: Significant benefits were found by implementing policies within the transport sector.

Sir Andy Haines: We modelled impacts in London and Delhi particularly by introducing more efficient private cars and also by increasing active transport, that is to say walking and cycling in particular. What we found is that both in London and Delhi this could have substantial benefits for public health - for example, reducing ischemic heart disease, cebro-vascular disease, dementia, some types of cancer and particularly in the case of Delhi, diabetes as well. That is because many of this diseases are related to inactivity, and of course to obesity as well.

Veronica Reimer: The food and agriculture sector is thought to be responsible for about 10-12% of global green house gas emissions and these are set to rise by up 50% by 2030. This is driven by the production of livestock to meet the increasing global demands for animal source foods.

Sir Andy Haines: The clear indication is that in high consuming countries, moderate and achievable reductions in animal product consumption could benefit the environment as well as potentially improving population health, by reducing saturated fat intake.

Veronica Riemer: WHO's Diarmid Campbell-Lendrum says that many of the actions we need to take to reduce greenhouse gas emissions will bring important co-benefits.

Dr Campbell-Lendrum: I think there has been an appreciation within the last few years that we can no longer see climate change as just an economic issue or just as an environmental issue – this is really a discussion about protecting the life support systems for human life as well as all other forms of life on earth.

Veronica Riemer:If you would like to read the Report of the international task force or to obtain related information, there are links on the transcript page of this podcast episode. Look for the link to the podcast on the home page of our web site, at

That's all for this episode of the WHO podcast. Thanks for listening. If you have any comments on our podcast or have any suggestions for future health topics drop us a line. Our email address is

For the World Health Organization, this is Veronica Riemer in Geneva.

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