A complex web of human development
Much like they defy our socio-economic divides, pathogens do not respect species boundaries. Researchers now believe that by reducing natural barriers between pathogen-carrying animals and ourselves, we humans are actually creating the conditions for the spread of not only inter-community, but also interspecies diseases.
In a recent article for Ensia, environmental editor John Vidal chronicled a trip he took to northern Gabon 16 years ago, in order to investigate why deadly diseases new to humans — namely the devastating Ebola outbreak of the late ‘90s — “were emerging from biodiversity ‘hotspots’ like tropical rainforests and bushmeat markets in African and Asian cities.”
Vidal, like all visitors, spent a day in a canoe and traveled for several hours down degraded logging roads and past a small mining operation, before he reached the small village of Mayibout 2, where 21 of 37 infected villagers had been killed by the Ebola virus in 1996 — an outbreak that was ultimately traced back to a chimpanzee from a neighboring forest.
The spread of infectious diseases from animals to humans is nothing new of course. Rabies and plague made the interspecies jump centuries ago. West Nile and Zika first appeared in the early 1950s. Lassa fever emerged in Nigeria in 1969. Ebola came in 1996, the bird flu in ’97, Nipah in ’98, SARS in 2002, MERS in 2012, and as we now suspect, COVID-19 in 2019.
“‘The disruption of pristine forests driven by logging, mining, roading building in remote regions, rapid urbanization, and population growth is bringing people into closer contact with animal species they may have never been near before,’” Kate Jones, chair of ecology and biodiversity at University College London, told Vidal.
According to Jones, the emergence of interspecies diseases is now “‘a hidden cost of human economic development.’”
“‘There are just so many more of us, in every environment,’” Jones told Vidal. “’We are going into largely undisturbed places and being exposed more and more. We are creating habitats where viruses are transmitted more easily, and then we are surprised that we have new ones.’”
Disease Ecologist Thomas Gillespie nodded to the U.S., where the clearing of forestland to create suburb communities has raised the risk of humans contracting Lyme disease from nearby ticks.
Yet, as Vidal writes, disease ecologists are also linking animal-to-human pathogen jumps to “the many informal markets that have sprung up to provide fresh meat to fast-growing urban populations around the world,” where “animals are slaughtered, cut up, and sold on the spot.”
“‘Wet markets,’” informal markets that sell both fresh produce and meat, “‘make a perfect storm for cross-species transmission of pathogens,’” Gillespie told Vidal. “‘Whenever you have novel interactions with a range of species in one place, whether that is in a natural environment like a forest or a wet market, you can have a spillover event.’”
But can we really demonize, let alone get rid of, the hundreds of thousands of informal markets that provide food for the hundreds of millions of global poor — the social have-nots — who lack access to refrigeration?
“‘Getting rid of them is impossible,’” Delia Grace, a senior epidemiologist and veterinarian with the International Livestock Research Institute based in Nairobi, Kenya, told Vidal. Grace further argued that wet-market bans only force traders underground, where they may pay even less attention to hygiene.
No pun intended, the connections between urbanization, informal markets, and the spread of interspecies pathogens is not always so clear-cut. Rather, as Vidal’s article suggests, the link between the emergence and spread of newly infectious diseases remains bounded by vast and complex web of human development.
The fossil fuel connection
Drawing parallels between the five waves of cholera that erupted between 1817 and 1896 — under humanity’s “first wave of globalization” — and the current COVID-19 pandemic, Author and Senior Lecturer at Tel-Aviv University On Barak believes that modern-day pandemics depend on fossil fuels to spread at the truly global rates we see today.
“What transformed a local contagion in a wet market in Wuhan into a pandemic within a matter of months is a network that begins with ground transportation within the infected regions and ends with the sea-and-air lines — all powered by fossil fuels,” Barak recently wrote for Quartz.
“An epidemic closes factories and grounds airline and marine transportation, slows economic growth, and reduces the demand for energy,” he continues. “These effects result in declining oil prices and could potentially ignite price wars that collapse the stock markets.”
In effect, the virus “now demobilizes the very system that facilitated its spread.”
Tracing the roots of the 19th century cholera epidemics, Barak references the evolution of the steam engine and the ships, newly powered by coal, that began transporting people and supplies across the world’s oceans faster than ever before. As put by Barak, advances in speed began to combat nature’s pull of the seasons.
What’s more, rather than spending long weeks in the open sea, steamers were required to make weekly refueling stops. Refueling stations of the 19th century were not unlike airports today — facilitating “the movement [of people and pathogens] between cold and warm places in a closed system of bubbles,” Barak continues, creating an “artificial archipelago” which has paved the way for the unprecedented scale of the COVID-19 pandemic we now face.
Barak further argues that the hesitation of the United States to close its borders and enforce quarantine measures that would hurt its economy seems to “stand on the shoulders of British imperial trade ideology.”
Almost immediately after the first wave of cholera erupted, Ottoman health authorities sought to combat the spread by quarantine measures. But Great Britain cried foul in “the name of free trade and the freedom of movement,” Barak explains.
In the later part of the century, the “natural right to open up new markets” fueled the Opium Wars, whereby Britain’s SS Nemis — the first coal-powered warship to cross the Indian Ocean — ultimately forced China to allow the free trade of opium.
“Opium and coal addiction blended with one another, infecting China, which has since been able to wean itself only from the former,” writes Barak. “Despite the ubiquitous assumption that cholera and coal are relics of the past,” he continues, “we remain entrenched in the age of coal and its mentality.”
In the wake of the current COVID-19 pandemic, we have witnessed slowed production, slowed economic growth, and a reduction in the demand for energy. The welcome environmental by-products of this global slow-down include the clearing of air pollution over major cities like Wuhan and the reduction of greenhouse gases.
But as Barak warns, “coronavirus is not a distress call from Mother Nature to stop global warming. It is another symptom of the system that produces it, a motion sickness indicating that the carbon-based world we assembled is contaminated in more ways we care to admit.”
Abigail Faires (@abbyfaires_lnks) is a freelance writer, international educator, and the co-founder of Learn2Link: a global learning network that inspires youth-led community development and emerging 501(c)(3) organization.