The Endangered Wildlife Trust (EWT) implements a range of initiatives that contribute to mitigating and reducing the impacts of climate change through our programmes across southern and East Africa. Among these are projects to address the impact of climate change on the health of communities.
Human health is inextricably linked to biodiversity and environmental health, with the World Health Organisation (WHO) confirming in a report published in October 2024 that climate change presents a fundamental threat to human health.
Climate change not only affects the physical environment and functioning of vital ecosystems that buffer us from extreme weather events and directly contribute to human health, but its effects on social and economic conditions are increasingly undermining human health and well-being. The WHO report states that climate change is a threat multiplier that is reducing and potentially reversing decades of health progress.
Humanitarian emergencies such as drought, heatwaves, wildfires, floods, tropical storms, and hurricanes are increasing in scale, frequency, and intensity. These weather and climate hazards affect health both directly and indirectly, increasing the risk of deaths, non-communicable diseases, the emergence and spread of infectious diseases, and other health emergencies.
In the past decade, extreme weather events have impacted approximately 1.6 billion people and cost the global economy over USD 2 trillion, according to a recent report released by the International Chamber of Commerce. The WHO reports an average of 489,000 heat-related deaths each year between 2000—2019, with these types of deaths having risen by 70% in people over 65 in two decades. The WHO conservatively projects 250,000 additional yearly deaths by the 2030’s due to climate change impacts, including increases in diseases like malaria.
Climate change is also exacerbating water insecurity globally, particularly as increasing populations and high demand are already stretching water allocations in most countries. Similarly, climate change heightens food insecurity, particularly in areas where people depend on dryland agriculture. In 2020, 98 million more people experienced food insecurity compared to the 1981–2010 average, with 770 million facing hunger, predominantly in Africa and Asia, undermining previous progress in addressing this challenge.
The Intergovernmental Panel on Climate Change’s (IPCC) Sixth Assessment Report (AR6) reveals that 3.6 billion people already live in areas highly susceptible to climate change. Despite contributing minimally to global emissions, low-income countries and small island developing states endure the harshest health and livelihood impacts. In vulnerable regions, the death rate from extreme weather events in the last decade was 15 times higher than in less vulnerable ones.
WHO data further indicates that 2 billion people lack safe drinking water and 600 million suffer from foodborne illnesses annually, with children under 5 bearing 30% of foodborne fatalities. Climate stressors heighten waterborne and foodborne disease risks. Temperature and precipitation changes enhance the spread of vector-borne diseases. Without preventive actions, deaths from such diseases, currently over 700,000 annually, may rise.
Climate change also adds to immediate mental health issues such as anxiety, as well as post-traumatic stress and long-term disorders, and compounds social instability, polarisation, and conflict, particularly in cases of human displacement.
Although no-one is safe from these risks, the people whose health is being harmed first and worst by the climate crisis are those who contribute least to its causes, and who are least able to protect themselves and their families against it: people in low-income communities and vulnerable countries and communities. Capturing risks like drought and migration pressures into climate modelling remains challenging, but there is little doubt that urgent, meaningful action is required at national and international level, focusing on the most vulnerable societies while also addressing the root causes of human-induced climate change.
Addressing climate change’s health burden underscores the equity imperative: those most responsible for emissions should bear the highest mitigation and adaptation costs, emphasising health equity and the priorisation of the vulnerable sectors of society.