Original article written by Sari Kovats of the London School of Hygiene and Tropical Medicine The impacts of climate change for health in Europe are discussed in this overview.

Introduction

Many diseases are affected by weather so it is not surprising that climate change may have varied impacts on our health. This article provides a comprehensive introduction to this issue. It is a useful starting point for anyone wishing to get an overview or to understand why some aspects of climate change are difficult to predict.

How might health be affected by changes in the climate?

Sections in this article

Environmental Factors which affect our Health

The range of health impacts

Insects and Disease and Flooding

Conclusions

Where Next?

Environmental Factors which affect our Health

Our health is profoundly affected by various natural systems such as food yields, water supplies, weather patterns and the ecology of pests and other organisms that cause disease. Climate change will affect human health simultaneously with other important, global, changes - such as urbanisation, environmental degradation, population growth and movement and technological change. All these factors can increase or decrease our vulnerability to the health impacts of climate change.

Lack of fresh water has implications for human health and water supply, especially in drought prone areas of Southern Europe

The link between weather and disease is illustrated by the seasonality of many diseases. Until the early part of this century, ‘summer diarrhoea' was a major cause of childhood deaths in Europe. What we have to identify is the impact of long-term climate change that will be manifested through changes in climate variability. Climate change is defined when the mean state of the climate or its variability alters significantly, persisting for an extended period (typically decades or longer).

The range of health impacts

Global climate change would have a wide range of potential health impacts - some positive, some negative. Globally, negative health impacts are anticipated to outweigh positive health impacts. Clearly, the worst effects will be felt in the poorer countries, both within Europe and beyond. Some health impacts would result directly from increases in heat waves and increases in floods, droughts and storms. A reduction in cold spells would reduce winter mortality in many cold and temperate countries. Climate change may also affect the local profile of air pollution (particularly photochemical smog) and aeroallergens (pollen).

A pensioner enjoying the health benefits of later autumns

Assessing the potential health effects of climate change involves many uncertainties. Researchers must consider future scenarios of climate change that have been derived from global climate models. However, these often fail to give us enough detailed information at the national or local scale. We also have to keep an eye on other, sometimes interrelated trends over the coming century which will have the most significant impacts on health: population growth and urbanisation, deforestation, economic growth and equity. Changes in our socio-economic conditions will have a major effect on our vulnerability to climate change.

Insects and Disease and Flooding

The spread of mosquitoes to areas with no natural immunity is a worry.

Some infectious diseases transmitted by insects (such as mosquitoes) are particularly sensitive to weather conditions. It is unlikely that "tropical" diseases such as malaria or dengue would become re-established in Western Europe if control measures are maintained - however, the risk of localised outbreaks of malaria may increase. In other parts of the world a shift in mosquito populations to areas where people haven't developed resistance to malaria could lead to devastating epidemics. Changes in climate may affect the distribution of some tick-borne diseases in Europe: Lyme disease may undergo a net expansion, whereas tick borne encephalitis may undergo a net contraction. The distribution of Leishmaniasis, which is transmitted by sandflies, may expand north within Europe.

Major impacts of climate change on human health in Europe are likely to occur via changes in the magnitude and frequency of heavy rainfall and associated river flooding. The changes in risk of coastal flooding will also be significant if no adaptive measures are taken. Floods are the most common trigger for a natural disaster in Europe. There is an increasing trend in the impacts (both social and economic) of weather-related disasters in Europe and globally indicating that populations are becoming more rather than less vulnerable.

Conclusions

Societies will need to adapt in order to minimise the adverse effects on health, safety, and social well-being. We need to fund research in areas such as monitoring and integrated assessment to help us better to predict and detect the early health impacts of climate change.

Policy options to reduce potential health impacts include the strengthening of public health programmes, such as vaccination for diseases such as tick-borne encephalitis if that is judged to be the most effective approach. A co-ordinated pan-European surveillance system needs to be developed to detect changes in incidence/distribution of infectious diseases associated with environmental or climate change. There are also implications for policy-making in the various "upstream" sectors that would mediate some of the effects of climate change on health. The management of water supply, industry, construction, and agriculture all have their role to play in mitigating the impacts.

Where Next?

On ClimateX.org

Two articles that may be of interest to anyone considering the health impacts of climate change are, ‘Death In the Marshes' about research into the risk of malaria in the British Isles and ‘Health Ups and Downs of Climate Change' which looks at some of the health pros and cons of warmer weather in the UK.

External links

To read about current research into the impacts of climate change on health for the UK, visit the UK Climate Impacts Programme at http://www.ukcip.org.uk/resources/sector/default.asp?sector=8