The Impacts of Climate Change on Global Human Health

by Olivia Draycott

Between 2030 and 2050, climate change is expected to cause approximately 250,000 additional deaths per year from malnutrition, malaria, diarrhoea, and heat stress [1]. This is due to a combination of increasing global temperatures, rising sea levels, and desertification. This is resulting in the displacement of animals, plant species and people from their homes [2], and increases the uneven distribution of environmental harm they are exposed to [3]. As a consequence, these citizens are at a greater risk of being exposed to zoonotic diseases, due to unfit living conditions that lack adequate sanitation [4].

Zoonoses have increased in frequency at a similar rate as climate change, with the former being aggravated by the latter [5]. The change in global temperatures has proven increasingly concerning in this regard, with African regions “currently experiencing the ideal temperature for transmission of malaria” [6]. Additionally, the rise in temperature has an undesirable impact on the health and wellbeing of citizens, who are experiencing greater rates of heat stress. This issue is further worsened by mass migration of citizens to urban areas, after their prior place of settlements become uninhabitable due to desertification due to rising temperatures [7]. The consequence of these two trends, has increased the frequency of zoonoses as well as other health risks experienced by the precarious situated urban populations. There is an urgent need for basic actions towards improving living conditions in cities as well as socio-environmental measures to reduce the risk of diseases [4]. 

Additionally, those in arid environments are not the only ones exposed to increasing health risks.  Global temperature rise leads to the melting of the earth’s permafrost exposing those in tundra environments to unseen risks such as the Orthopoxvirus species Alaskapox that causes skin lesions  [8]. This  virus species  has appeared and disappeared in Alaska twice between 2017 to 2022, creating concerns about the effect  of climate change induced warming on microbial repositories in global permafrosts and a yet to be understood range of consequences [8].

Alongside the increase in global temperatures, rising oceanic sea levels are indirectly posing a significant threat to global health [9]. The increase in worldwide water temperatures enhances the danger of a mass relocation of species and creates environments where waterborne zoonoses such as schistosomiasis, cercarial dermatitis, fascioliasis, and fasciolopsiasis thrive [10]. Additionally, it leads to a homogenization of global biodiversity that harms the oceanic ecosystem and interspecies relations. The resulting cross-over between species previously isolated from one another furtherincreases the risk of transmittable diseases. 

A third way of climate change threatening human health is through the deterioration of water quality globally, with landlocked countries facing the problem evermore [11]. Reducing the groundwater levels and volume of water in rivers has the harmful consequences of water insecurity and disparity between those who have access to it and those who do not [12]. Additionally, an increase in storm surges and other disasters flooding freshwater storage and aquifers contaminates the water already present within them, resulting in a vast expenditure of resources and money to restore them to their previous state [12].

Drastic measures must be taken to reinforce measures currently in place for the protection of biodiversity and ecosystems [13]. Instead of trying to deal with the health consequences of the climate crisis, long term measures to prevent and mitigate these consequences from occurring in the first place must be taken [14]. To this end, the World Health Organisation advocates measures that focus on reducing greenhouse gas emission through investing in greener and more efficient transport and food production, alongside investment into renewable energy sources [15]. The negative consequences of climate change can also be mitigated through small yet effective long term infrastructure changes such as flood defence barriers and water permeable pavements to better deal with floods and stormwater [16]. Efforts to reduce the global health consequences of climate change have occurred in countries such as the UK where schemes such as the Shoreline Management Plan (SMP) attempt to reduce and mitigate the impacts of rising sea levels and potential risk of interspecies disease transmission. The SMP proposes ‘managed realignment’ to create new habitat areas that will act as a natural buffer to coastal erosion as well as preserving habitual areas to prevent unnecessary encroachment and forced correspondence between species [17]. 

Reference List

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