“This is not just about the environment, it’s about the community, it’s about jobs, it’s about justice.”  

– Eddie Bautista

As the current pandemic continues to shed light on the stark inequities in our society, it becomes abundantly clear that these inequalities are present in various other areas (Mastroianni, 2021). The pandemic also clearly demonstrates how our health is closely linked to the social, political, physical, and natural environments that we live in.

The recent natural disasters such as the wildfires across North America and the flash flooding that devastated parts of central Europe – all point to a single cause, climate change. Climate change is a major public health concern and impacts our health both directly and indirectly.

Most often, the ‘ice caps melting’ narrative of climate change overlooks the social and economic impacts and fails to recognize how climate change, food security, education, access to healthcare, and other social and cultural determinants of health are intertwined (Galvão et al., 2009). 

The social determinants of health pertain to the social circumstances in which people are born into, live, work, and age, including factors such as poverty, structural racism, housing instability, education, and employment status (Braveman et al., 2011).

These determinants are shaped by the distribution of money, power, and resources at local, national, and global levels, and disproportionately impact individual and population health (Braveman et al., 2011). As climate change becomes more widely recognized as a public health issue, it is becoming increasingly difficult to separate it from the list of determinants that worsen health outcomes, increase healthcare cost and expenditure, and disproportionately impact vulnerable communities (Levy & Patz, 2015).

Some researchers are starting to consider climate change not only as a social determinant of health, but perhaps the most important social determinant (Strunk & Bibbins, 2019). The Intergovernmental Panel on Climate Change (IPCC) claims that by 2050 climate change will exacerbate existing health problems with increases in respiratory, cardiovascular diseases and premature death (Woodward et al., 2014), leaving those who are vulnerable at the greatest risk (Smith et al., 2014).

Climate change is a threat multiplier meaning as a social determinant of health, it threatens human health by worsening air quality, increasing the burden of climate sensitive diseases, increasing food and shelter insecurity and so on (Bhor & Kumar, 2016). 

The adverse health outcomes associated with climate change are extensive. Public health experts and scientists have highlighted the impact of the changing climate on health for a long time now, with the first established link between climate change and human health made in the 1990s by Anthony McMichael (Harmer et al., 2020). In this blog post, we will be highlighting:

1. The direct health impacts of climate change 
2. The indirect health impacts of climate change and the social determinants of health
3. Preparing and managing a climate resilient health system?

The direct health impacts of climate change

Health consequences of climate change are extensive and can influence an array of health outcomes. The IPCC estimates that climate related illness will be the greatest risk in the future and climate change will also exacerbate existing health problems (Smith et al., 2014).

Changes in the climate also means changes in the frequency, intensity, and duration of extreme weather events (Ebi et al., 2017). Heat stress is considered one of the main direct impacts of climate change on human health, with the prevalence of heat-related deaths increasing due to climate change affecting  respiratory and cardiovascular diseases (Paavola, 2017).

Globally, temperature related mortality presents a significant burden, with over 5 million people dying as a result of extreme temperatures (Lu & Cox, 2021). In the UK, mortality increases by 2.1% for every 1°C increase above the average yearly temperature (Paavola, 2017). As temperatures are expected to continue increasing, this burden is also likely to increase. 

Depletion of air quality due to increased ground ozone levels is associated with increased morbidity and mortality due to respiratory issues (Ebi et al., 2017). Changes in the climate also affects levels of pollen; increased temperatures increase pollen season and weather events such as thunderstorms can transform pollen into biological aerosols leading to increased incidence of allergies and worsening asthma outbreaks (Ebi et al., 2017). Extreme weather events such as flooding increases the incidence of drowning, electrocution, accidental death, and injuries (Ebi et al., 2017). 

Climate disruptions can have a major impact on mental health. Research has primarily focused on the physical implications of climate change, however, changes to the natural landscape, extreme weather events, and food disruptions can give rise to changes in personal lives and on mental health.

Displacement, increase in violence, abuse and financial stress due to climate change can all contribute to mental illness worsening individuals and community’s quality of life (World Health Organization, 2019).  Climate change can trigger anxiety, depression, post-traumatic stress disorder (PTSD), and other mental health illnesses (Hayes et al., 2018). In an article titled ‘Climate change and mental health’, Trombley et al., describe various ways in which climate change can lead to negative mental health outcomes, in regards to climate related disasters as well as the implications of gradual climate decline (Trombley, Chalupka & Anderko, 2017). 

Contaminated water sources can lead to increases in food-borne diseases. Warmer temperatures are linked to increased cases of Salmonella worldwide and enables more rapid replication and higher rates of infection (Akil et al., 2014). Furthermore, rising temperatures can create ecological disruption that favour the spread of vector-borne diseases such as malaria, dengue, and Lyme disease resulting in higher burden of disease on people and health systems (Ebi et al., 2017) (Paavola, 2017).

Impacts of Climate Change on Human Health

The indirect health impacts of climate change and the social determinants of health

The health impacts of climate change will not have the same impacts on everyone. The link between climate change and inequities is explicit; climate change will not only disproportionately impact vulnerable populations; it will also worsen pre-existing social and health inequalities (Phelps et al., 1996). 

The indirect health impacts of climate change are and will continue to disproportionately affect, and have more severe impacts, on marginalized communities, including communities of colour. People of colour and those of low socioeconomic status (SES) often live in neighbourhoods with more polluted air and fewer hospitals (Mastroianni, 2021).

This increases the likelihood of respiratory diseases like asthma that are exacerbated by climate change, and offer limited options for treatment. In some urban areas in the UK, poor air quality has been shown to exacerbate asthma, especially in children, leading to fatal outcomes as in the case of Ella Adoo-Kissi-Debrah (BBC News, 2020).

During severe weather events, poorer infrastructure in those neighbourhoods leads to greater impacts on the health of individuals, their families, and their communities. The lack of resources creates challenges for recovery, meaning that it is often a slow and long road, leading to additional increases in morbidity and mortality (Quinn, 2006). 

Research following Hurricane Katrina found that low-income survivors experienced severe mental and physical health consequences (Rhodes et al., 2010). Similarly, persons belonging to minority ethnic groups, older people, those with disabilities, and those from low SES background experienced poorer health outcomes following the impact of Hurricane Harvey (Flores et al., 2020).

Preparing and managing: Is there such a thing as a climate resilient health system?

A climate resilient health system aims to “enhance the capacity of health systems to protect and improve population health in an unstable and changing climate” (World Health Organization, 2019). The WHO’s framework for climate resilient health systems presents a comprehensive response to climate change.

This framework outlines objectives for providing a systemic approach, focusing on areas such as health workforce, integrated disease surveillance and early warnings, sustainable technologies and infrastructure, and climate informed health programmes (World Health Organization, 2019). 

Climate change is a global issue and current plans for building a resilient health system tend to be a “one size fits all” approach. This can be problematic, especially for low-income countries. A low-income country, prone to extreme weather events like Bangladesh will have different needs and approaches to developing and implementing a resilient health system initiative (Rahaman et al., 2019) compared to Australia, a geophysically stable high-income country (FitzGerald et al., 2019).

Social and cultural differences between these countries must also be considered when implementing climate resilient health systems, as well as national capacity and political will.

Conceptual framework for resilience (Operational framework for building climate resilient health systems, 2015)

Given these realities, can there ever be such a thing as a climate resilient health system? Health systems will need to be prepared to deal with the immediate and long-lasting casualties of climate change. While currently proposed ideas are a start, there are knowledge and capacity gaps that will need to be addressed to increase the equity of responses to climate related injuries (Yoong, 2020).

Take Home Message

Individuals, communities, and nations face major health and well-being difficulties as a result of climate change. Preventing, preparing for, and managing climate-related hazards to human health will be a recurring subject as climate injustice worsens.

While the immediate health impacts related to climate change appear clear, the covert social and economic impacts of climate change are also important considerations in order to build stronger and resilient health systems.