Environmental Pandemics

Why Climate Change is a Necessary Component of the Discussion on Infectious Diseases

By: Dylan Macy

During the current global pandemic, COVID-19, in which almost every country in the world was exposed within three months after cases first reported in Wuhan, China, a topic that is likely not at the forefront of many minds is climate change. Understandably, many have been more concerned with keeping their selves and their families safe, bracing for a looming global recession, and stocking up on medical supplies and groceries.

Prioritization of the acute economic crisis brought on by COVID-19 over the broader, more long-term crisis of climate change is evident in the United State’s indefinite loosening of federal environmental regulation in March, 2020. More specifically, this policy decision fails to address how a degraded environment will lead to an increased likelihood of future pandemics and populations more susceptible to virus complications. 

1. Long-term pollution and unequal declines in population health 

A popular “glass-half-full” approach to the COVID-19 pandemic is addressing the environmental benefits that national-stay-at-home mandates have exhibited. Chinese greenhouse gas emissions dropped by 25%, the water in the Venice canals is clean enough for dolphins to swim through, and notoriously car and smog-ridden Los Angeles has been reporting some of the cleanest air among major cities due to social distancing measures.

Finding sources of optimism is a valuable endeavor during these uncertain times. But, taking these supplemental occurrences to then make claims about COVID-19 helping to combat climate change neglects the long-term commitment that must be made to reduce global emissions and those already suffering from the climate-change-disease interface. The World Meteorological Organization (WMO) estimates a 6% drop in global greenhouse emissions — the most significant reduction since World War II — as a result of slowing industrial economies in the age of COVID-19. Although, it is important to remember that reductions in emissions do not actually remove greenhouse gases from our atmosphere, as some of the most abundant gases such as Carbon Dioxide (CO2) and Nitrous Oxide (N2O) can stay present in the atmosphere for centuries. More importantly, this acute dip in emissions is just that: a short-term, downward trend in global emissions that have been increasing for 150 years due to human activity. 

Like many topics during this pandemic, speculation runs high. While some believe that this pandemic will create lasting environmental changes, many experts speculate that emissions will rebound — if not increase — as countries’ economies get back on track. China, for example, after seeing a near 25% reduction in emissions due to coronavirus measures is now seeing a slowing of declines in emissions as the economy steadily opens. 

COVID-19 has resulted in a dip in greenhouse gas emissions, but depicting this trend as a “silver bullet” for the global environment largely underestimates the long-term damage that humans have already done to the climate. In other words, a year-long dip in emissions will do effectively nothing for protecting the planet against anthropogenic climate change. Furthermore, members of the public that see COVID-19 as a victory for environmental concerns are not seeing the full picture, as research is showing that the populations dying from COVID-19 at the highest rates are those who have also been disproportionally affected by the various manifestations of climate change, specifically air pollution. 

Who makes up these populations? Communities of color and low-income families. The American Lung Association compiled research that indicates exposure to harmful, long-term air pollution is highest in areas with large populations of people of color, low-incomes, and low property values. Living in these highly-pollutive areas and breathing harmful air particles over time has been linked to developing and worsening chronic lung diseases, particularly asthma which is one of the primary pre-existing conditions that can lead to fatal COVID-19 complications. What’s more, a recent study by Harvard University found that the counties in the United States with high levels of air pollution have the highest COVID-19 mortality rates, suggesting a possible causal relationship between air-pollution-exposure and COVID-19 fatality. 

Take all of the forces alluded to above: systemic racism, environmental injustices linked to respiratory ailments, and the current public health crisis. Identifying the intersection of these forces, one can understand the case-study of Louisiana better, where 70.5% of the people who have died from the COVID-19 are African Americans in a state with some of the worst air quality and whose African American population is just 33%. In light of this knowledge, it seems truly irresponsible for officiating bodies such as the EPA to loosen environmental regulations during this pandemic. If environmental degradation is likely to exacerbate COVID-19 exposure/complications risks, disproportionally affect communities of color, in conjunction with increasing evidence that industrial polluters will ignore any environmental safety requirements, this governmental mandate puts some of the country’s most vulnerable at additional risk during very uncertain times.  

2. Climate Exacerbating Agents on Viruses 

A second connection between global climate change and pandemics is transmission. Humans have transformed landscapes in ways that favor the transmission of infectious diseases from wildlife populations into humans. Recent history has shown that many viruses that emerge in human populations are zoonotic (i.e. diseases that are transferred from animals to humans). Research has found that at least 60% of diseases that emerged during 1960-2004 have origins in non-human animals. These zoonotic diseases include everything from HIV/AIDS, Ebola, Zika, as well as the 2003 SARS coronavirus , which shares similarities to the current COVID-19 coronavirus, such as the way it enters the human body through respiratory cells, its likely origin in bats, as well as its stability in air and on surfaces. Researchers at the Wuhan Institute of Virology additionally found that the COVID-19 genome is 96 percent genetically identical to the 2003 SARs virus, which has origins in horseshoe bats in Southern China.  

One of humanity’s primary safeguards against zoonotic transmission is biodiversity. When forests and other habitats are cleared for the sake of industrial agriculture, many species die off, biodiversity declines, and the few species that remain tend to be capable of asymptomatically carrying infectious diseases. Just between the period of 1990 and 2016, the globe lost 502,000 square miles of forest — an area larger than South Africa — due to human-caused deforestation. The decline in the world’s forest cover reduces the power trees have to sequester atmospheric greenhouse gases, maintain healthy ecosystems, and limit the transmission of infectious disease from wild animals to humans. 

Deforestation shrinks the buffer (biodiverse forests) between wildlife and human operations, agriculture for example, in a way that increases the likelihood of zoonotic disease transmission. Species that thrive and rapidly reproduce in these deforested and barren ecosystems include wild birds (responsible for the West Nile Fever) and smaller mammals such as bats and rats (responsible for diseases such as Ebola and Rabies). Scientists now have confidence and an emerging consensus that COVID-19 originated in bats in southern China. The origins of COVID-19 are still not definitively known. But, understanding how COVID-19 can pass from bats to animals that were transported to the “wet market”  in Wuhan will be an important part of making the link between climate change drivers and zoonotic disease emergence in the future. 

Agricultural deforestation has been, and continues to be, a result of a growing global  population. On average, the global population is getting richer in addition to expanding. Historians and researchers have found that as populations become more affluent, consumption of animal products increases. In the context of infectious disease, this is problematic as animal agriculture is responsible for the most intense rates of deforestation, shrinking the zoonotic disease transmission buffer zone at the fastest rate and increasing the likely transmission vectors as agricultural animals are put into more densely confined lots, worsening living conditions, and closer proximity to non-domesticated animals carrying infectious diseases. Additionally, American workers at meat-packing plants are some of the most at risk of contracting the virus (rates of infections are 75% higher near these plants than other counties around the country) due to sub-optimal working conditions, the volume of workers required to be in close proximity to one another, and a dangerous insistence on keeping these plants open by the federal government due to American’s perceived dependence on meat

In a world where agriculture currently occupies almost one half of the world’s landmass (with a projected need to double or triple operations by 2100 to feed the growing population), the question must be addressed of how the industrialized infrastructures of our food systems, which rely on deforestation and very unsanitary animal living conditions, will put our global ecosystem and population at worsening risks of climate change and zoonotic disease transmission. 

3. Global Food Systems and Infectious Diseases

Furthermore, COVID-19 is a singular data point in the long history of zoonotic diseases. To assume that closing wild-life markets and blaming different cultures’ taste for “exotic meats” will prevent the next pandemic is a drastically naive notion. The wildlife trade will always lead to an increased risk of zoonotic transmission, especially if said wildlife shares habitats with species very capable of carrying infectious diseases, such as the horseshoe bat. But, humans are steadily clearing habitats and thus putting themselves and domesticated livestock in closer proximity to species that carry infectious disease, creating barren, non-biodiverse landscapes that allow virus-host animals, such as bats, to thrive. 

More tightly regulating the illegal wildlife trade and un-sanitary open-air markets is a step, not the answer, to minimizing the threat of future zoonotic disease transmission.

At a global level, resources are being engulfed by industrial agriculture practices at alarming rates. Governments and business leaders will eventually need to find ways to farm more efficiently so that the entire globe is not converted to agricultural land in order to feed a population skyrocketing towards 9 billion. At an individual level, we can kickstart this process by advocating for more deforestation safeguards and eating less meat, as animal agriculture currently occupies 60 percent of the world’s arable land, is responsible for a third of all biodiversity loss, and makes up 14.5 percent of all anthropogenic greenhouse gas emissions.

The global magnitude of animal agriculture and its harmful impacts are drastic and will quite literally be unsustainable once the global population swells to 9 billion and above. 

The increased likelihood of harmful zoonotic disease spawning and spinning out of control will be one result of unchecked animal agriculture expansion. Continued toxic emissions will continue to harm vulnerable populations at disproportionate rates and put them more at risk of developing complications with infectious diseases as time moves forward. Our environment — what we put into it, how we try to transform it, where certain populations are located — will always be interconnected with diseases, such as COVID-19, that challenge us as a species to survive. Let us minimize the health and economic dangers of future pandemics, not by suspending environmental laws or placing entire blame on the Chinese wildlife trade, but by more closely caring for our environment at global, national, and individual levels. After all, the environment is a tested and true safeguard against disease transmission, a supplier of clean air and water, and the home to every living organism. Working with the environment is our only chance of healthily sustaining life as our population grows throughout the 21st century. Let us care and raise awareness for the environment and its biodiverse habitats. Let us help prevent the next pandemic. 

Written in Spring 2020 by Dylan Macy, Pitzer ‘20.

About the Author: Dylan is a senior at Pitzer College pursuing a double major in Media Production and Environmental Policy, with a particular interest in how mainstream media informs how the public talks about environmental issues. Dylan is originally from Boston, Massachusetts and hopes to work within environmental communications upon graduating.