The Climate Change Health Crisis
More than half of known human infectious diseases can be aggravated by climate change. Apathetic political leaders aren't just condemning us to extreme weather's devastation – they're condemning us to perpetual health crisis, too.
Red Cross workers don PPE prior to burying a three-year-old boy suspected of dying from Ebola on 13 October 2022 in Mubende, Uganda. (Luke Dray / Getty)
A year on from the much reported-on COP26 in Glasgow, which saw world leaders under growing pressure to take substantial action on climate change and was derided by many as a failure, COP27 took place this month in Egypt’s Sharm el-Sheikh. And, in the process of that year, world leaders appear to have become no more serious about tackling climate change, maintaining a level of evasion and inaction that’s sending us heading towards 2.5 C.
This is as true of the UK as anywhere. Some governments have tried to increase their decarbonising efforts, including improving their energy efficiency, a process made as necessary by the cost of living crisis as the climate. But countries like the UK have opted for an alternative route, using soaring energy costs to justify their apathy.
The science on the impacts of climate change has never been more certain. In August 2021, the Intergovernmental Panel on Climate Change (IPCC) published the first part of its tripartite sixth report, which warned that without ‘immediate and deep’ emissions reductions across all sectors it will be impossible to contain average global temperature rise to 1.5C above pre-industrial levels. The third part, published in March 2022, reviewed the vulnerabilities to which we are prone as the extreme impacts of climate change go ahead.
The situation in terms of extreme weather is already dire. Record heatwaves ravaged the globe this summer, resulting in Europe’s biggest and longest droughts and wildfires; Hurricane Ian caused irreparable damage in Cuba, the US, and other places in the Americas and the Caribbean; and more recently floods in Pakistan, Nigeria, Niger, Bangladesh, and South Sudan have left livelihoods wrecked, families and communities uprooted, and thousands of people needlessly dying.
But this isn’t all we have to fear. In addition, the IPCC report warned that without swift climate action, we’ll see a resurgence of a range of infectious diseases. It’s thought that they will spread to new regions and surge in areas in which they had been previously contained. It’s also expected that zoonotic diseases will increase, with more diseases that have never previously infected humans spilling over from animals. This is supported by the review of systemic studies published in Nature Climate Change, the results of which are unnerving: more than half of known human infectious diseases are aggravated by climate change.
An Infectious Planet
Global warming can have both direct and indirect effects on illness. Direct effects include heat shock and increased mortality, especially in ageing populations and those with comorbidities. Indirect effects include aggravating infectious diseases. It’s the indirect effects which are more worrying given their long-term impacts, and how far-reaching they can be for entire populations.
The link is multifaceted. Global warming and increased rainfall could result in disease vectors that can expand their geographical range—mosquitoes, for example, or ticks, or birds—being exposed to human populations they’ve never previously interacted with. What’s more, the disruption and destruction of habitats, especially those high in biodiversity, drives wildlife like rodents and primates to find new homes, which can bring them closer to human habitations, making zoonotic exposures more likely. The thawing of permafrost of the arctic soils in Siberia in 2016 caused pathogens like anthrax to be unleashed, causing a deadly outbreak: over two thousand reindeer contracted it, and passed it on to the nomadic Nenets people.
The rising cases of mosquito-borne diseases like malaria, gastric infection, and dengue fever in Pakistan exemplify this process. Floods have devastated the country this year, leaving several areas underwater for months. The aftermath has resulted in wastewater overflow, compromising safe drinking water and spreading pathogens, leading to a rise in noroviruses, rotavirus, and cholera.
Pakistan has reported that the floods have affected 33 million in its 230 million-strong population, hitting its drier southern provinces hardest. The Directorate General of Health Services reports that between July and early October, nearly 350,000 people had malaria, more than 700,000 experienced diarrhoea, and over 770,000 people reported a skin-related disease. This had its own knock-on effect on tracking and containing other diseases like polio and measles, which could be a major blow to the process Pakistan has made at eradicating the diseases. Alongside Afghanistan, it’s one of two countries where polio is still endemic.
The floods that occurred in Nigeria, said to be the worst recorded in their history, tell a similar story. Nigeria has seen flooding every year for the last decade, just one of the many West African countries experiencing the worst effects of the climate crisis. Collectively, African countries contribute a mere four percent of global emissions but carry the burden of displacement, mass loss, and damage. And despite the risk of infectious diseases like cholera spreading, especially in untreated waters, many of those left to fend for themselves in the aftermath of the floods are being forced to use the stagnant floodwaters to drink, cook, clean, and wash. Not only does this foretell an increase in the incidence of infectious diseases, but it is overwhelming hospitals across the country—and even forcing them to shut down.
Environmental Inoculation
Climate change will spell disaster for the health and wellbeing of all, but its impact will differ vastly region by region. Higher temperatures might decrease the likeliness of vector-borne diseases spreading in warmer places like the Global South, for example, but it will increase the spread of them in colder areas including the Global North, while the scale of that impact will be dependent on factors like the robustness of national infrastructure and the wealth countries that have to rebuild after disease and disaster.
Considering how nationalism and profit margins took precedence during the ongoing Covid pandemic, leading even to use of the term vaccine apartheid, it’s only natural to assume that whatever challenges Global South countries face, they will once again be left to fend for themselves. Despite that, the responsibility for what is happening in Pakistan right now, for example, lies largely with countries in the Global North, which collectively represent 80 percent of global emissions. Pakistan, by comparison, contributes less than one percent.
The reality is that we can’t afford to fight this problem on a state-by-state basis, especially when inequality between those states is so stark: infectious diseases, just like hurricanes and heatwaves, do not stop for national borders. That’s a fact world leaders should have learned from our failures during the Covid-19 pandemic, but they refuse to. The danger to our health highlights not only the unaccounted-for impacts of the climate crisis, but also that of poor disaster planning globally. And what’s true of disasters past is true of those coming down the track—that doing nothing is a death sentence.