Climate Change & Human Health

An average temperature rise of just two degrees centigrade will have a catastrophic impact on human health. It will be the most vulnerable societies, and the most vulnerable people within those societies, who will suffer most. This makes tackling climate change at all levels – individually, organisationally, locally, regionally and globally – a public health imperative and an urgent priority for NHS leadership.

The health impact of climate change is already being seen around the world. The World Health Organization (WHO) estimated that the climate change that occurred between 1961 and 1990 – a global temperature increase of just 0.6 degrees centigrade – is causing, each year, 150,000 deaths and the loss of 5.5 million Disability-Adjusted Life Years. Importantly, these estimates may not reflect the true scale of the mortality and morbidity as a consequence of climate change. The IPCC lists major health effects of climate change, which are "likely to affect the health status of millions of people" across the globe. And The Met Office reports that, ‘Climate variability and change cause death and disease 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.’

Nationally, as highlighted in ‘Department of Health, Health Effects of Climate Change in the UK 2001’ and the updated 2008 version, climate change poses the following health risks to the UK population, which will clearly have a direct impact on NHS Trusts: 

• Climate models now predict a temperature increase of 2.5 deg C and 3 deg C by the end of the 21st century. There will be fewer periods of very cold weather but more heat waves. Warming from 1971 to 2002 has caused reduced cold-related mortality but so far in the UK heat-related mortality has not increased. However, the 2003 European heat wave caused an estimated 14,000 premature deaths in Northern France. It is estimated that by 2012, each year there will be a 1 in 40 chance that a heat wave in South East England would kill over 9,000 people if preventative measures were not taken.
• Cases of food poisoning due to warmer weather are likely to increase significantly, by perhaps 10,000 cases annually.
• Climate change will affect drinking water supplies, through increased rainfall (leading to more bacteria in surface water), increased water temperature (causing an increase in algal blooms in reservoirs), and a decrease in the efficiency of chemical coagulation, which is one of the methods used to remove microbes from drinking water.
• The concentration of ozone is likely to increase over the next 50 years, partly as a result of climate change and partly as a result of air pollutants. This will lead to several thousand extra deaths and hospital emissions.
• Higher temperatures, more sunshine and less rain as a result of climate change are likely to lead to more outdoor activity and higher exposure to the sun, which would lead to higher incidences of skin cancer and cataracts.