Climate change and human health

Climate change is a significant and emerging threat to public health, and changes the way we must look at protecting vulnerable populations.

Olav A. Saltbones/Norwegian Red Cross

The Intergovernmental Panel on Climate Change has presented overwhelming evidence that human actions are contributing to global warming and other changes in the climate system, with a wide range of implications for human health. Climate variability already causes death and injury through natural disasters, such as heatwaves, floods and droughts. In addition, many important diseases are highly sensitive to changing temperatures and precipitation. These include common vector- borne diseases such as malaria and dengue; as well as other major killers such as malnutrition and diarrhoea. Climate change already contributes to the global burden of disease, and this contribution is expected to grow in the future.

The impacts of climate on human health will not be evenly distributed around the world. Developing country populations, particularly in Small Island States, arid and high mountain zones, and in densely populated coastal areas, are considered to be particularly vulnerable.

Fortunately, much of the health risk is avoidable through existing health programmes and interventions. Concerted action to strengthen key features of health systems, and to promote healthy development choices, can enhance public health now as well as reduce vulnerability to future climate change. In addition, many of the actions that are necessary to reduce greenhouse gas emissions can also bring very large public health benefits, for example through reduced air pollution.

WHO has an active and long-standing programme on protecting health from climate change, guided by a World Health Assembly resolution. Through its country, regional and headquarters offices, WHO provides evidence and supports capacity building and implementation projects to strengthen the health system response to climate change, and to ensure that health is appropriately considered in decisions made by other sectors, such as energy and transport. The Organization also provides the health-sector voice within the overall UN response to this global challenge.