The 11 day United Nations conference on climate change opening in Bali on 3 December will shed new light on the degree of importance that policy makers attach to public health as they seek ways to mitigate the gradual increase in the world's temperature and prepare for the consequences.
The final part (a synthesis) of the fourth assessment report of the UN Intergovernmental Panel on Climate Change (IPCC) confirms that the trend towards global warming can no longer be questioned.
“Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level,” notes the synthesis, which was released on 17 November (see www.ipcc.ch).
The chapter devoted to health issues confirms that humans are being directly exposed to climate change through new weather patterns and indirectly through alterations in water, air, and food quality and evolving ecosystems. Emerging evidence points to changes in the distribution of some vectors of infectious disease and in the seasonal distribution of some allergenic pollen species.
More specifically, the report predicts with a high degree of confidence that there will be more deaths, disease, and injury from heat waves, floods, storms, fires, and drought; greater malnutrition; higher cardiorespiratory morbidity and mortality associated with ground level ozone; and changes in the range of some vectors of infectious disease.
It points to an increase in diarrhoeal diseases and in the number of people at risk of contracting dengue fever. The geographical range of malaria may contract in some areas but expand in others. There may be fewer deaths from hypothermia in the northern hemisphere, but this is likely to be outweighed by the negative effects of rising temperatures, especially in developing countries.
Sari Kovats, of the London School of Tropical Medicine and Hygiene, one of the lead authors of the chapter on health, said, “Each country should assess how climate change will affect its population. We are not really there at the moment. We need more health impact assessments at the local and national level.”
The World Health Organization, which produced its first report on climate change and public health 17 years ago, is looking for a strong signal at Bali that the potential effects of extreme weather conditions on humans and health systems will receive greater attention than in the past.
Diarmid Campbell-Lendrum, a senior scientist in WHO's public health and environment department, said, “WHO would like to see a strong commitment to the need for health protection from climate change, since it will involve additional health risks and extra costs on health services. But this commitment must not be at the expense of continuing our unfinished agenda of tackling existing challenges such as the high burden of disease in Africa.”
He believes that discussions on climate change have gone through three stages. At first they were mostly concerned with the effect on the environment, then they moved on to include development issues, and now they are embracing this wider dimension of the health implications.
“At heart it is about protecting individuals' lives and livelihoods. That is the real reason most people are concerned and the reason that we are now starting to see health arguments increasingly put forward as among the most important reasons to act against climate change,” he explained.
WHO is playing a growing role in highlighting the health implications of climate change. Earlier this year Margaret Chan, its director general, said that climate change “may turn out to be the most ominous struggle” facing health care in the coming years.
In early December Dr Chan will make a major speech on the subject in the United States. WHO regional committees are focusing on the issues that the phenomenon raises, and next year the theme for world health day on 7 April, which coincides with WHO's 60th anniversary celebrations, will be the protection of health against climate change.
The European Union has also made tackling climate change one of its major political priorities. The European Commission is preparing a consultative white paper for next year. This will assess the effects on health of heat waves, floods, and extreme cold; infectious diseases; air pollution and airborne allergies; and ultraviolet radiation.
Robert Madelin, the head of the commission's directorate general on public health, says that “joined-up thinking” is needed.
He explained: “If [the problem] is a critical thing like a heat wave and lots of old people die, then it is very much down to the health systems [to cope]. If you are looking at vectorborne diseases, then a mixture of pest control and public health [will be needed].”
He outlined what EU policy makers could do to mitigate the worst effects of climate change. “In order to avoid nasty consequences of climate change, you need to have better pest control. Then you have extreme weather conditions, so you have to have health service preparedness. Those would be the two main threads.”
The Health and Environment Alliance, a Brussels based network of some 50 non-governmental organisations aiming to show how environmental protection can improve health, recently set out a series of policy recommendations.
The alliance advises EU policy makers to:
Ensure that European subsidies mitigate the effects of climate change rather than contribute to such change
Guarantee that any measures taken benefit health
Provide practical assistance to countries on the EU's borders, and
Support networks that help identify the risks involved and raise public awareness.
The alliance would also like to see WHO further develop its data collection and analyses of the health effects of climate change, estimate the costs to health in individual European countries, and gather case studies of initiatives being taken by non-governmental organisations to adapt to and prepare for the consequences of climate change.
Tackling climate change has a silver lining, said Dr Campbell-Lendrum. “Our message from the health point of view is that this is a threat, but it also gives us an opportunity to rethink our relationship with the environment. We know that if we can improve our management of the environment—and climate change is part of this—then we can bring about a 25% reduction in the global burden of disease.”
At the same time the health sector itself can take initiatives that will make it more energy efficient and reduce outputs of dangerous gases. In the UK the government has established the Carbon Trust to help NHS hospitals cut their carbon emissions. It found that hospitals can cut their carbon imprint by 20% on average in a five year implementation plan.
In Germany the environmental group BUND provides information and a certificate scheme for energy saving and climate protection in hospitals.