Climate and health: the link is close.

• Climate change is taking a hidden toll on global health that requires urgent action.
• The health impact is disproportionately suffered by the poorest and most vulnerable populations, who contribute least to climate change.
• The World Economic Forum’s Climate and Health Initiative is a first step towards greater recognition of and action on this issue.

For the first time in its 28-year history, the United Nations Climate Summit, this year known as COP28, has included a day on climate change’s impact on health. It is hardly surprising, given record climate change-related weather events over the past two years that have killed tens of thousands around the world and cost the global economy billions, if not trillions.

The world tends to view climate change through the lens of monetary losses from the damage caused by the last catastrophic storm or out-of-control wildfire. But the most severe impacts of climate change lie ahead in the immense perils to life and health we will face in the not-too-distant future.

The danger from climate change is truly existential, considering the number of deaths that are likely to be attributed to it. Ultimately, the growing body of evidence on these threats to public health must be turned into concrete policy and action, with a focus on the need for resiliency and the ability to mitigate negative effects from global warming.

Unequal burdens

Complicating the public health response is the fact that climate change won’t affect regions equally. The distribution of deaths and economic losses falls heaviest on the poorest and most vulnerable populations – a particularly tragic and ironic fact given that this population contributes the fewest greenhouse gas emissions. Official lists of countries most affected by climate change are dominated by African nations, which have suffered years of rising temperatures and inadequate rainfall while simultaneously experiencing massive downpours that have led to flooding. Yet the continent only accounts for 4% of global emissions.

Take South Sudan. The country’s temperatures are increasing at two and half times the global average. This has resulted in extreme weather events, including four consecutive years of flooding in half of the nation, and years of inadequate rainfall in the other half. The UN’s World Food Programme estimates that 64% of its 12 million people are suffering from severe hunger stemming from these dual impacts.

But suffering from climate change isn’t restricted to one region. Worldwide communities are facing a roster of threats – from droughts to flooding, severe tropical storms and rising sea levels, to prolonged heatwaves and wildfires.

Dry and wet threats

Let’s start with drought. One of the most life-threatening of the climate-related weather events, drought progresses slowly compared with floods, hurricanes and wildfires. Yet it still leads to higher levels of malnutrition causing the stunting of growth and development among children, and an array of pervasive infectious diseases.

About 55 million people annually face drought conditions, and 40% of the world contends with water scarcity, according to the World Health Organization (WHO). An estimated 700 million are at risk of being displaced as a result of drought by 2030.

While droughts involve too little water and floods involve too much, their impact on public health is sadly not that different. Both destroy food and water sources as well as a region’s crops, livestock and livelihoods. In 2022, Pakistan was inundated by an extreme monsoon season – which led to flooding that affected 33 million people, half of whom were children. More than 5 million people were forced to use contaminated water from wells and streams. A year later, the nation still has almost 15 million people suffering from severe hunger.

Vector-borne diseases – those carried by organisms like mosquitoes and ticks – account for more than 17% of all infectious diseases and kill more than 700,000 people annually, according to the WHO. Extreme climate and weather patterns such as droughts, heatwaves, floods and rainfall extend breeding seasons and territory for mosquitoes, ticks and other vectors.

This means climate change could help spread viruses like malaria, dengue and Zika to higher latitudes and expose more people. A 2019 research study found that by 2050, the two primary disease-spreading mosquitoes will significantly expand their range, posing a threat to 49% of the world’s population.

Worst year on record

Another major impact from climate change has been the increasing ferocity of storms worldwide. The frequency, duration and severity of tropical storms is expected to intensify as ocean temperatures climb. There have been three Category 3 or higher hurricanes in 2023, which makes it officially the worst year on record for billion-dollar-plus weather events.

Wildfires are another growing phenomenon as high temperatures dry out foliage and produce conditions ripe for blazes. Besides immense destruction of property and loss of life and livestock, wildfires worldwide are aggravating air pollution, which in turn exacerbates respiratory ailments as well as cardiovascular diseases. Research suggests that air pollution will lead to 6-9 million premature deaths per year by 2060, and there could be as much as a 50% increase in mortality from heat-related cardiovascular disease.

Finally, all climate-related disasters can create a sense of anxiety, loss and helplessness when confronting the uncontrollable forces of nature, leading to depression, alcohol and drug abuse, and post-traumatic stress disorder. For these reasons, we anticipate the incidence of mental health illness to rise precipitously because of climate change, at an anticipated cost of $6 trillion by 2030 to cover treatment and productivity loss.

Is the global health community prepared? Like COVID-19, climate change is likely to be countered with too few resources and inadequate capacity to handle an onslaught of disease and despair from global warming. This will require stakeholders – from governments and non-governmental organizations, to private enterprises such as pharma companies, medtech innovators and healthcare providers – to drive solutions and public-private partnerships that will take concrete steps to reinforce the readiness of healthcare systems. Additionally, the necessary time, financial and intellectual investments must be made to support the work.

Some work has started through organizations like the WHO, which has released national adaptation plans to help countries measure the impacts of climate change and implement health-related policy. But these impending crises must be addressed with more urgency and evidence-based research that can help shape interventions aimed at increasing the preparedness and resilience of health systems, communities and vulnerable populations.

The World Economic Forum’s Climate and Health Initiative is also tackling the climate-health connection by shaping high-impact solutions and incentivizing the necessary long-term financial support and private funding that must be at the crux of any global healthcare response.

In addition, the initiative is helping to develop the kind of quantification and analysis that will identify the populations most at risk, so the healthcare community might proactively address the threats. We can act now to bolster the infrastructure and push the vaccines that should be developed or drugs that need more production capacity.

Unlike COVID-19, we have a chance to get ahead of the problem. We should take it.

Article written by :

Shyam Bishen - Head, Centre for Health and Healthcare; Member of the Executive Committee, World Economic Forum

Rolf Fricker - Senior Partner, Health and Life Sciences, Oliver Wyman

Oliver Eitelwein - Partner, Health & Life Sciences, Oliver Wyman

This article is part of : Centre for Health and Healthcare