Godbharle Swapnil R., M.Sc. Health Sciences, Savitribai Phule Pune University, Pune, India.
The good health of the populations depends on the continued stability and also the functioning of the biosphere’s ecological and physical systems, also known as the life-support systems. The world’s climate system is an integral part of life-supporting processes that are now coming under pressure from the increasing weight of human numbers and their economic activities.
Over the last 50 years, human activities like burning of fossil fuels have released high quantities of CO2 and other greenhouse gases to trap additional heat in the lower atmosphere and affect the global climate. Sea levels are rising, glaciers are melting and the precipitation patterns are also changing frequently. Extreme weather events are becoming more frequent and intense. Climate change along with other natural and human-made health stressors, affects human health and disease in numerous ways. Some existing health threats will intensify and also the new health threats will also emerge.
- Climate change particularly affects the environmental and social determinants of health like clean air, secure shelter, sufficient food, and safe drinking water.
- Between the year 2030 and 2050, climate change is expected to cause about 250,000 additional deaths per year, due to malaria, diarrhea, malnutrition, and heat stress.
- Mostly the developing countries will be the least able to cope without assistance to prepare and respond.
- 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.
What is the impact of climate change on health?
- Extreme high air temperature contributes directly to deaths from cardiovascular diseases (CVDs) and respiratory diseases, particularly among the elderly population. For example, in the heat wave of summer 2003 in Europe, more than 70,000 excess deaths were recorded.
- Pollen and other aeroallergen levels are also higher in extreme heat. These can trigger asthma, which affects around 300 million people.
- Globally, the number of reported weather-related natural disasters has more than tripled since the 1960s. Every year, mainly in developing countries these disasters result in over 60,000 deaths.
- Increasingly variable rainfall patterns are likely to affect the supply of fresh water. Due to a lack of safe water hygiene will be compromised and the risk of diarrhoeal diseases will increase, which kills about 760,000 children aged less than 5, every year.
- Rising temperatures and variable precipitation are likely to decrease the production of staple foods in many of the poorest regions. These conditions will increase the prevalence of malnutrition and undernutrition, which currently cause 3.1 million deaths annually.
- Climate conditions strongly affect the water-borne diseases and diseases transmitted through insects, snails or other cold-blooded animals.
- Changes in the climate conditions will lengthen the transmission seasons of the important vector-borne diseases.
Who is at risk?
All populations will be affected by climate change, but some are more vulnerable than others. Populations living in Small Island, developing countries and other coastal regions, megacities, and mountainous and polar regions are more vulnerable. The health effects are expected to be more severe for children and elderly people-in particular, those living in poor countries.
Measures to reduce the impact of climate change on health
- Make sure that the existing public health surveillance systems are sufficiently comprehensive and sensitive enough to detect the minute potential effects of climate change on health.
- Establish and effectively implement the heat warning systems and air cooling systems and take steps to increase public awareness of the consequences of heat exposure.
- Air quality monitoring and management.
- Increase the awareness of climate change and its impact on health among public health and medical practitioners.