5 Ways Climate Change Affects Global Health


As attention turns to the COP26 meetings in Glasgow, the reality of climate change had been front of mind for millions long before it became a political priority. The health of our planet and that of humanity are inextricably linked.


According to the World Health Organization, from 2030, climate change is expected to contribute to approximately 250,000 additional deaths per year. Nobody is immune to the impacts of climate change, but resource-poor countries have weaker healthcare systems, putting more lives at risk from the effects of climate change.


5 ways that our changing climate is causing dire health consequences:


1. Infectious diseases

Malaria kills over 400,000 people worldwide every year. Malaria infections are seasonal and our changing climate affects its spread in a number of ways, including the life cycle and behaviour of infection-carrying mosquitos. Heavier rainfall creates an environment for breeding, and rising temperatures affect their geographic spread. This year saw a breakthrough in the prevention of malaria with the launch of a new vaccine to reduce its spread, but climate change risks rolling back the impact of such advances.


Dengue, schistosomiasis and other infectious diseases are also becoming a greater risk as the insects, snails and water that carry them are affected by changing weather patterns.


2. Respiratory diseases

“Climate change represents a massive direct threat to respiratory health by promoting or aggravating respiratory diseases or indirectly by increasing exposure to risk factors for respiratory diseases” - European Respiratory Review

People living with asthma are facing increased triggers such as increased pollen. The direct economic impacts of climate change perpetuate the practice of using open wood stoves for household cooking, a common practice in Malawi, increasing the risk of chronic obstructive pulmonary disease. Forest fires, increasingly common as droughts become more frequent, pollute the surrounding air, affecting all those with respiratory problems.


“Nearly 740,000 access deaths in India annually can be attributed to abnormal hot and cold temperatures related to climate change,” reported India’s Hindu Times. The rising frequency and severity of heatwaves are a direct threat to the life of vulnerable groups, including those with respiratory diseases. The 2003 heatwave in Europe led to a reported 70,000 excess deaths. Mortality data is gravely lacking in resource-poor countries, meaning that we can’t know the full extent of extreme heat in recent years, but it is a growing threat for the future.


3. Nutrition and food security

Many populations depend on rain-fed agriculture. For example, in Malawi, 90% of agriculture depends on rain for irrigation. Such countries are highly vulnerable to changes in rains, temperatures and severe weather. Chronic undernutrition is a threat to the health and prosperity of many and affects 37% of under-5s.


Access to reliable and nutritious food determines long-term health and affects education and household productivity significantly. For people living with life-limiting illnesses, nutrition is an important part of long-term care and crucial to the efficacy of essential medicines.


4. Natural Disasters

The devastating effects of climate-linked natural disasters in Europe are being seen particularly through flooding. More than 200 people died in floods in Germany and Belgium earlier this year and the risk of these tragic incidents is rising. Climate crises are, sadly, all the more familiar to resource-poor countries, as they have weaker national coping systems and weaker regulation, for example permitting housing on land prone to flooding or landslides.

“Globally, the number of reported weather-related natural disasters has more than tripled since the 1960s. Every year, these disasters result in over 60,000 deaths, mainly in developing countries.” - WHO

Globally, Nepal is ranked fourth and thirtieth in terms of vulnerability to climate change and flood risks respectively. Late monsoon rains have cost over 150 lives in Nepal and India in one week in October 2021 alone. Natural disasters also destroy livelihoods, roads to essential services and healthcare infrastructure - climate change makes the hardest-to-reach, even harder-to-reach.


5. Water and Sanitation

In a time of COVID-19, we’ve become acutely aware of the need for water and basic sanitation for regular handwashing. However, a recent survey of health facilities in Mulanje district, Malawi, showed that 8% had no safe, reliable running water, while 23% had limited water for use by patients for bathing, cooking and toilets. The changing climate means that boreholes dry up and water supplies become contaminated during floods.


Climate change is expected to add to water shortages and the challenges of improving access to clean water and sanitation. This carries a number of risks for people’s health and wellbeing. It also adds to the burdens on women and girls who are mostly responsible for gathering water.


Urgent change is needed

These are some of the more direct impacts of climate change, but its influence is wide-reaching. National budgets of agriculture-based economies are also affected, as economies stagnate when crops fail, then so do budgets for healthcare systems. And those who rely on subsistence farming toil harder to feed their families, damaging their health while the costs of travel to healthcare or medication become increasingly unaffordable ‘luxuries’.


These are just some of the ways that climate change is affecting global health. They are all areas where risks are growing and will continue to grow without decisive global action. COP26 isn’t a conference on temperatures, carbon and weather patterns - it is about lives and livelihoods. The decisions at COP26 and our collective actions will be measured in the health of some of the world’s poorest communities.