Climate change and health

The poorest people, particularly those living in the global south, are the most directly dependent on the environment’s resources (such as food crops, water, wood and fish) for their livelihoods. In Africa, for example, agriculture accounts for two thirds of the workforce and around half of household income and food. Threats to the sustainability of the environment directly threaten to increase poverty and malnutrition.

But as well as threatening livelihoods through changes in freshwater supplies and crop yields, climate change will also affect the spread of disease; increase the number of extreme weather events such as heat waves, floods, and fires; and permanently displace millions of people.

‘Developing’ countries will be worst affected partly because of geography and partly because they lack the resources to adapt quickly to the impacts of climate change. As temperatures increase and rainfall patterns change, crop yields are expected to drop significantly in Africa, the Middle East and India, while densely populated coastal areas and small island states will be particularly vulnerable to floods. Increased flooding will spread more water-borne diseases like diarrhoea, while droughts will breed insects and rodents affecting food, water supplies and health. With rising temperatures, diseases like malaria, West Nile disease, dengue fever and river blindness will shift to new areas.

How many people will be affected?

By 2080 up to three billion people could suffer increased water shortages, and up to 70 million more people in sub-Saharan Africa alone could be living in areas prone to malaria. An extra one billion people could be at risk of dengue fever. Already, estimates suggest that 150,000 people are dying each year as a result of climate change.

Climate change also threatens new inter-state conflict over access to natural resources, and will certainly result in millions more migrants and refugees in the years ahead.

Wealthy countries must act faster to reduce their emissions, and national governments must start developing plans now to adapt to the effects of climate change. Strengthening existing health systems should be the starting point for addressing the health risks from climate change.