COP28 plans the event’s first-ever Health Day. Here's why it's important

For the first time ever, the COP28 UN Climate Conference will hold a dedicated “Day of Health”. It’s a sign of the growing recognition of the profound impact climate change has on human health and how, in today's interconnected world, the consequences of climate change are felt far beyond the degradation of the environment.

More and more, experts are calling for attention to this connection. In fact, October 2023, 200 medical journals published a call for the environmental crises of climate change and biodiversity loss to be recognised and treated as a health emergency. Failure to deliver mitigation and adaptation action across all sectors will result in catastrophic health-related losses and damages in every region of the world, including injury, disease and associated healthcare costs, death, damage to healthcare infrastructure, and reduced economic outputs.

Ahead of this year’s Day of Health at COP28, here are five ways climate impacts health.

Climate change exacerbates air pollution, the largest environmental health risk, with severe implications for health. Air pollution and greenhouse gases often come from the same source - gases and particles emitted to the atmosphere from a variety of human activities, such as the inefficient combustion of fuels or the open burning of waste, agriculture and farming.

Higher temperatures contribute to the formation of ground-level ozone and fine particulate matter, both of which can cause direct health effects, including the exacerbation of respiratory conditions, such as asthma and chronic obstructive pulmonary disease, and increased incidence of lung cancers. Poor air quality is also strongly linked to non-communicable diseases, including heart attacks, strokes and diabetes. Air pollution can also be caused by natural sources - many of which are impacted by human activities, for example, wildfires, soil dust and salt in sea spray.

As temperatures soar to unprecedented levels, heat-related illnesses and deaths are becoming alarmingly more prevalent. Heatstroke occurs when the body can’t cool itself down and prolonged exposure to extreme heat can lead to heat exhaustion, heatstroke and even death. A recent study in the American Heart Association journal Circulation stated that between 2008 and 2019, extreme heat was associated with 1,651 excess cardiovascular deaths in the US each year. It predicts that these deaths could increase by up to 233% annually due to climate change over the forthcoming decades.

Heatwaves also worsen air quality, which has knock-on effects on human health, ecosystems and agriculture and especially affects the most vulnerable, including the elderly, children, pregnant women and those with pre-existing health conditions. Wildfires, which are a growing concern in many parts of the world due to prolonged droughts and rising temperatures, release harmful pollutants into the air, further compromising air quality. Protecting respiratory health requires concerted efforts to reduce emissions, transition to cleaner energy sources and more sustainable land management practices.

Climate change has a direct impact on the distribution and behaviour of disease-carrying vectors, such as mosquitoes and ticks. Rising temperatures and altered precipitation patterns, including flooding and heavy rainfall, create conducive environments for these vectors to thrive and expand their territories. This, in turn, leads to the proliferation of diseases, such as malaria, dengue fever and Lyme disease, in regions previously unaffected.

As these diseases spread to new areas, healthcare systems are confronted with challenges they may not be adequately equipped to handle. The burden on already strained healthcare infrastructure can be immense, underscoring the urgency of proactive measures to combat climate-driven vector-borne diseases.

Shifts in climate patterns disrupt agricultural systems, leading to reduced crop yields, food shortages and increased food prices. The food-water nexus is one of the most critical to address, with food systems representing 72% of total water withdrawals. Water insecurity, therefore, not only threatens health via direct access to water, but also risks food security and overall wellbeing. Malnutrition, both undernutrition and overnutrition, can result from reduced access to diverse and nutritious foods.

Furthermore, climate-related disasters, such as floods, droughts and hurricanes, can destroy crops and contaminate water sources, heightening the risk of foodborne illnesses. Addressing these challenges necessitates a multifaceted approach, including sustainable agriculture practices, investment in resilient food systems and the promotion of dietary diversity.

The psychological toll of climate change cannot be underestimated. Natural disasters, displacement due to sea-level rise and the uncertainty of a changing climate can lead to increased stress, anxiety, depression and post-traumatic stress disorder. Vulnerable populations, including those living in poverty and marginalized communities, are disproportionately affected. Additionally, the loss of livelihoods and homes due to extreme weather events can lead to long-term mental health challenges. Recognizing and addressing the mental health impacts of climate change is essential for building resilient communities and fostering well-being.

The link between climate change and human health is undeniable. The urgency to act cannot be overstated. From heat-related illnesses to the spread of vector-borne diseases, the consequences of a changing climate are already affecting communities around the world. It is imperative that we prioritize mitigation and adaptation strategies, invest in resilient healthcare systems and work collectively to safeguard the health and wellbeing of current and future generations.

Considering the impact on health from air quality, funding for air pollution remains low. Only 2% of international public climate finance intentionally tackled air pollution in 2015-2022, according to the Clean Air Fund. Every $1 spent on air pollution control can yield an estimated $30 in economic benefits, as the US Environment Protection Agency found, which underscores the urgent need for increased funding in clean air projects. By curbing air pollution, societies can reduce healthcare costs, boost worker productivity and create new opportunities for innovation and sustainable development.

Integrated finance and action for climate change and health necessitate recognition of synergistic action for a more resilient and sustainable future. This requires collaboration among policymakers, financial institutions, health professionals and communities to effectively address shared challenges and opportunities. Through concerted efforts, we can build a healthier, more sustainable future for all.