WHO / Michalis Karagiannis
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Climate change and health

30 May 2025

Key facts

  • The WHO European Region is the fastest-warming region globally and the impacts of climate change here are clear. 2024 was the warmest year on record for continental Europe, with record temperatures in its central, eastern and southeastern regions. The last 10 years have been the warmest 10 years on record. 19 of the 23 most severe heatwaves in Europe since 1950 occurred since 2000.
  • Significant numbers of additional deaths every year are due to heat. In 35 countries in the Region, more than 61 000 people died in 2022 and 47 000 in 2023 due to heat. Moreover, heat also causes an uncounted amount of suffering and impacts on well-being.
  • Climate change is projected to increase the number of days with high heat stress levels. The frequency, intensity and duration of heatwaves will increase further, seriously impacting public health in the Region. Heat-related mortality in the Region has increased by more than 30% during the past 20 years. The combined effects of climate change, urbanization and population ageing could substantially worsen heat-related impacts in the future.
  • In autumn 2024, heavy rainfall and flooding in Valencia, Spain, killed more than 200 people. Devastating flooding impacted wide areas of the Italian region of Emilia-Romagna in May 2023, with more than 38 000 people displaced from their homes. In July 2021, several countries in northwestern Europe were exposed to devastating floods, with more than 230 fatalities; Belgium and Germany were the worst affected, but communities in Luxembourg, Netherlands (Kingdom of the) and Switzerland also suffered damage and loss.
  • In the last 50 years, the 1672 reported weather-related disasters in the Region have led to about 160 000 deaths, with an estimated economic loss of US$ 477 billion. The most-reported causes of disasters were floods (38%) and storms (32%), but extreme temperatures led to the highest proportion of disaster-related deaths (93%).
  • While the intensity and frequency of heavy rain and flood events are likely to increase in many areas throughout the Region, European freshwater is also under significant pressure, posing challenges to short- and long-term water security. Water stress already affects 20% of continental Europe’s territory and 30% of the population every year – figures that are likely to increase in the future due to climate change.
  • Climate change continues to alter the distribution of disease vectors. Examples include ticks, which may transmit tick-borne encephalitis and Lyme disease and are now found at higher altitudes and latitudes; the tiger mosquito Aedes albopictus, which is responsible for the transmission of several diseases, including dengue, chikungunya and Zika, and has expanded its distribution; and sand flies, which transmit leishmaniasis and have also shifted their distribution.

Overview

The leading climate-related causes of death, illness and suffering result from exposure to increasingly frequent and more intense extreme weather events, including heatwaves, wildfires, floods and storm surges, as well as slow-onset events, such as droughts.

Climate change can also result in declining crop yields and, through the effect of increasing atmospheric carbon dioxide, reduced nutrient quality of crops, leading to increased malnutrition. Crop yields could decrease by 25–30% in central Asia and southern parts of Europe by the middle of the 21st century. Climate change affects the health of people in the Region in a myriad of ways, including through death and illness from increasingly frequent extreme weather events, such as heatwaves, storms and floods; increases in zoonoses and food, water and vector-borne diseases; indirect impacts on air quality, food and water security; and mental health issues.

Climate change is set to become the most challenging threat populations face in the coming decades and needs to be tackled urgently. A significant increase in ill health and premature deaths is projected due to climate change, with an additional 250 000 deaths per year worldwide by mid-century due to climate-sensitive diseases and conditions; under high-emissions scenarios, over 9 million additional deaths are projected per year by 2100.

In the Region, temperatures have increased by more than twice the global average over the past years – the highest increase of any continent in the world. This change in the climate is causing significant harm to both natural and social systems, resulting in extensive and profound effects on health and well-being.

Adaptation and mitigation measures are necessary to address the burden of disease due to current climate impacts and the additional burden posed by projected climate change. There is a need to strengthen mainstream public health and health services to bolster climate-resilient communities.

WHO response

WHO works with countries towards creating sustainable “well-being societies” that are committed to achieving equitable health now and for future generations without breaching ecological limits.

Through its European Centre for Environment and Health (ECEH), WHO steers the development of technical guidance of global relevance, including a second edition of WHO’s “Heat-health action plans guidance”.

It offers policy advice and provides technical support to build capacities in countries, including on climate change and health. WHO develops methods and tools, including those to assess health and economic gains due to climate change mitigation measures.

In particular, WHO supports countries to:

  • integrate health considerations in climate mitigation and adaptation decision-making and policies;
  • develop health adaptation plans and heat–health action plans;
  • raise awareness on healthy climate policies in all sectors;
  • strengthen early warning, surveillance and preparedness systems for extreme weather events and disease outbreaks;
  • strengthen the climate resilience of health systems;
  • reduce greenhouse gas emissions in the health sector and improve environmental sustainability;
  • advocate for strengthening the realization of the health co-benefits of climate change mitigation and air pollution reduction; and
  • share knowledge, research and tools for evidence-informed policy-making.

WHO ECEH provides secretariat functions to the Working Group on Health in Climate Change (HIC), established under the European Environment and Health Task Force. The HIC supports Member States in implementing commitments made under the European Environment and Health Process (EHP) and their national efforts to advance the climate change and health agenda.

The Declaration of the Seventh Ministerial Conference on Environment and Health, held in Budapest, Hungary, on 5–7 July 2023, places an emphasis on climate change and health that is unprecedented in the history of the EHP. The Budapest Declaration also established a new Member State-led mechanism for a Partnership for Health Sector Climate Action, which aims to provide a regional community of practice to share approaches, experience and research as countries chart pathways and solutions to developing climate-resilient, low-carbon and environmentally sustainable health systems.