Keywords: climate change, health, impact, vulnerability, adaptation
The health impacts of climate change and variability in developing countries
Health is a focus reflecting the combined impacts of climate change on the physical environment, ecosystems, the economic environment and society. Long-term changes in the world's climate may affect many requisites of good health - sufficient food, safe and adequate drinking water and secure dwelling. The current large-scale social and environmental changes mean that we must assign a much higher priority to population health in the policy debate on climate change. Climate change will affect human health and well-being through a variety of mechanisms. Climate change can adversely impact on the availability of fresh water supply and the efficiency of local sewerage systems. It is also likely to affect food security. Cereal yields are expected to increase at high and mid latitudes but decrease at lower latitudes. Changes in food production are likely to significantly affect health in Africa. In addition, the distribution and seasonal transmission of several vector-borne infectious diseases (such as malaria and dengue) may be affected by climate change. Altered distribution of some vector species may be among the early signals of climate change. A change in the world climate could increase the frequency and severity of extreme weather events. The impacts on health of natural disasters are considerable - the number of people killed, injured or made homeless from such causes is increasingly alarming. The vulnerability of people living in risk-prone areas is an important contributor to disaster casualties and damage. An increase in heatwaves (and possibly air pollution) will be a problem in urban areas, where excess mortality and morbidity is currently observed during hot weather episodes. We can assume that climate change will affect the most vulnerable in developing countries. These might be socio-economic deprived populations, people who lack access to a health care system, technology and communication, as well as immuno-compromised persons. The health community has, however, difficulties in clearly attributing changes in ranges of diseases or mortality to climatic changes. The main reasons are the gradual process of climate change, the multiple causes of diseases, the many factors that permit human population health to adapt and the lack of retrospective and prospective studies from developing countries. Adaptation is a key response strategy to minimise potential impacts of climate change. A primary objective of adaptation is the reduction, with the least cost, of death, disease, disability and human suffering. The ability to adapt to climate change impacts, and specifically of health, will depend on many factors including existing infrastructure, resources, technology, information and the level of equity in different countries and regions.