Impact of Climate Change on Health
Climate Change is a threat to public health. The social and environmental determinants of health-clean air, drinking water, adequate food supply and secure shelter, are affected by it. Changes in the concentration of greenhouse gases and other drivers alter the global climate and bring about a myriad of human health consequences. Environmental consequences of climate change, such as heat waves, rising sea levels, floods and droughts, intense hurricanes, and degraded air quality have direct and indirect impact on the health of humans.
Who is at Risk?
Certain people are more at risk of experiencing the health impacts of climate change than others, including those who:
• Are elderly, very young, disabled, poor, or living alone.
• Have existing medical conditions such as heart disease or asthma.
• Live in urban neighborhoods that are already stressed by air pollution, aging infrastructure, and the heat island effect, which makes cities hotter than surrounding rural areas.
The degree to which people will be affected also depends on the ability of a region to prepare for and respond to risks. Improvements in emergency preparedness, health-care systems, and other response measures can all help reduce the health impacts of climate change.
Impact of Climate Change on Health
- Global warming is allowing an array of forgotten pathogens to emerge from the thawing permafrost—and possibly reinfect humans. Organic matter like dead animals, moss and plants, long preserved in ice, are now thawing, rotting, and releasing gases that not only spur global warming but create a new breeding ground for bacteria and viruses.
- Climate change is making heat waves hotter and more frequent which can cause heat exhaustion and heatstroke or worsen pre-existing cardiovascular and respiratory conditions.
- Warmer temperatures in cities make city residents more prone to a heightened risk due to the urban heat island effect(caused by paved surfaces that absorb and re-radiate heat) and also due to the lack of tree cover and green spaces in these areas.
- The climate change and frequent El Nino affects the amount of carbon dioxide in the atmosphere by causing droughts that cut the ability of plants and trees to absorb it.
The direct damage costs to health (i.e. excluding costs in health-determining sectors such as agriculture and water and sanitation), is estimated to be between US$ 2-4 billion/year by 2030.— WHO
- The supply of fresh water is likely to be affected by increasingly variable rainfall patterns. A lack of safe drinking water can compromise hygiene and increase the risk of diarrheal disease, which kills over 5,00,000 children aged under 5 years, every year. Water scarcity can lead to drought and famine in extreme cases. It is projected that by the late 21st century, the frequency and intensity of drought are likely to increase at regional and global scale.
- Climate change has also affected the frequency and intensity of floods which are expected to continue to increase throughout the current century. Floods can further contaminate freshwater supplies and increase the risk of water-borne diseases. They are also known to create breeding grounds for disease-carrying insects such as mosquitoes.Diseases such as cholera and salmonella, which are transmitted through contaminated food or water, could become more widespread with climate change because of increased flooding.
- Changes in temperature and rainfall in some areas are likely to increase the range and the length of activity for ticks and mosquitoes, which can spread diseases such as Lyme disease, malaria, and West Nile virus.
Health Effects of Climate Change
Floods and Drought
Initiate or worsen respiratory, cardiovascular and other diseases
Heat stress and illness
Waterborne diseases, drowning and injuries
West nile virus, lyme disease, liver, respiratory, nervous and skin disorders
Heat related mortality
Threats to livelihood
Reduced productivity at workplace/school
Strain on essential services and disruption to key social networks
Respiratory ailments, wildfires
- Increasing temperatures, variable rainfalls and loss of agricultural land due to flash floods are expected to reduce crop yields in many tropical developing regions, where food security is already a problem.
- Increasing global temperatures affect both manmade and natural air-borne particles, such as plant pollen, which can trigger asthma. A study says that about 6% of children suffer from respiratory tract infection and 2% of adults suffer from asthma. If urgent actions are not taken, asthma deaths could increase by almost 20% in next 10 years.
- Climate change could also cause more severe allergy symptoms because a warmer climate is expected to promote the growth of the molds, weeds, grasses, and trees that cause allergic reactions in some people.
Reducing emissions of greenhouse gases through better transport, food and energy-use choices can result in improved health, particularly through reduced air pollution.— WHO
What Can be Done?
Health and environment cannot be dealt in isolation as they are intrinsically linked to each other. It is necessary to evolve adaptive strategies to cope with climate change. Following points should be taken into consideration:
- Strengthening existing emergency preparedness and disaster management programme for international health surveillance and monitoring systems. Multidisciplinary approach and collaboration with other agencies—such as agricultural, meteorological, environmental and planning agencies are essential.
- Promote the use of environmentally friendly fuels and healthy transportation system.
- Promotion of healthy environment housing.
- Promotion of emergency response system for sporadic climate change disaster.
- Health education and promotion programmes to incorporate health impacts of climate change on infectious diseases.
- Database and information system to be established for accurate monitoring and data collation.
- Vaccination campaigns for all possible diseases.
- Sustained and improved sanitary conditions in human settlements.
- Sustained and improved disease vector control.
- Regular cleaning campaigns need to be conducted for sites and places where mosquito vector is abundant.
- Conduct research programmes on the use of biological control.
- Promotion of hygienic waste disposal methods will help to prevent contamination with disease pathogens in the event of cyclones and floods.
- Management of surface water catchments will help to maintain the quality of domestic water and continuity of water supply.
- In view of considerable lack of data and expertise on the nature and magnitude of these impacts, it is important to undertake research both at population and individual levels so as to provide a solid basis for the formulation of adaptation strategies.
“Climate change affects every aspect of society, from the health of the global economy to the health of our children. It is about the water in our wells and in our taps. It is about the food on the table and at the core of nearly all the major challenges we face today.” —Ban Ki-Moon