Coronavirus pandemic linked to destruction of wildlife and world’s ecosystems

April 14, 2020

After the novel coronavirus broke out in Wuhan, China in late December 2019, it didn’t take long for conspiracy theorists to claim it was manufactured in a nearby lab.

Scientific consensus, on the other hand, is that the virus — SARS-CoV-2 — is a zoonotic disease that jumped from animal to human. It most likely originated in a bat, possibly before passing through another mammal.

While the virus was certainly not engineered in a laboratory, this doesn’t mean we haven’t played a role in the current pandemic. Human impingement on natural habitats, biodiversity loss and ecosystem degradation are making virus spillover events much more likely, a major new study from scientists in Australia and the US has found.

Read more: Coronavirus: Air pollution might raise risk of fatality

The number of emerging infectious disease outbreaks has more than tripled every decade since the 1980s. More than two thirds of these diseases originate in animals, and about 70% of those come from wild animals. Many of the infectious diseases we’re familiar with — Ebola, HIV, swine and avian flu — are zoonotic.

People in hazmat suits walk along a street in Wuhan

Contrary to what conspiracy theorists say, the novel coronavirus was not created in a lab in Wuhan, but the pandemic is linked to human behavior

Aided by a hyper-connected global population, SARS-CoV-2 and the disease it causes, COVID-19, has also demonstrated how quickly modern outbreaks can become pandemics.

While the speed at which COVID-19 has spread across the world has shocked many, scientists have long been warning of such a pandemic.

By disrupting ecosystems, we have created the conditions that allow animal viruses to cross over into human populations, says Joachim Spangenberg, ecologist and vice-president of the Sustainable Europe Research Institute.

“We are creating this situation, not the animals,” Spangenberg told DW.

Deforestation, habitat encroachment

As people move further into the territories of wild animals to clear forests, raise livestock, hunt and extract resources, we are increasingly exposed to the pathogens that normally never leave these places and the bodies they inhabit.

“We’re getting closer and closer to wild animals,” says Yan Xiang, professor of virology at the University of Texas Health Science Center, “and that brings us into contact with these viruses.”

An aeriel view of a denuded forest

After the Amazon, the tar sands in Canada are responsible for the second fastest rate of deforestation on the planet

Read more: Coronavirus: Can we still live sustainably?

“As you increase human population density and increase encroachment onto natural habitats, not just by people but by our domesticated animals, you’re increasing the rolls on the die,” David Hayman, professor of infectious disease ecology at Massey University in New Zealand, told DW.

But, as well as increasing the likelihood of transfer, ecosystem disruption also has an impact on how many viruses exist in the wild and how they behave.

In the last century, tropical forests, home to around two thirds of the world’s living organisms, have been halved. This profound loss of habitat has ripple effects throughout the entire ecosystem, including on the “parts we tend to forget — infections,” says Hayman.

In some cases, scientists have observed that when animals at the top of the food chain disappear, the animals at the bottom of the food chain, like rats and mice that carry more pathogens, tend to fill that space.

“It’s not just about how many species we have in an ecosystem,” says Alice Latinne at the Wildlife Conservation Society, “it’s about which species.”

“Each species plays a different role in the ecosystem and sometimes, if you just replace one species with another, this can have a huge impact in terms of disease risk. And sometimes we can’t predict it,” she told DW.

People in the Amazon

Between August 2018 and July 2019, nearly 10,000 square kilometers of the Amazon were cut down

Read more: NGOs fear COP26 postponement could scuttle climate change policy

Habitat changes can also force animals — and their pathogens — to go elsewhere, including areas populated by people.

Latinne draws on the example of the emergence of Nipah virus in Malaysia in the late 1990s, where deforestation drove fruit bats from their forest habitat to mango trees on pig farms. Bats often carry pathogens that don’t bother them, but in this case when the pigs came into contact with bat droppings and saliva, they became infected. The pigs then went on to infect farmers.

Evidence linking disruption of ecosystems to increased risk of novel infection transfer is why, Spangenberg says, experts talk about the importance of the “One Health” concept; the idea that the health of animals, the ecosystem and humans are all interlinked, and when one is out of balance, others follow suit.

Read more: Tough times ahead for climate protesters during corona pandemic

Wildlife trade

So-called “wet markets” selling produce, meat and live animals provide another incubator for the emergence of infectious disease. Scientists believe there’s a strong possibility SARS-CoV-2 emerged at a wet market in Wuhan, China.

Cramming stressed, sick animals into cages together is, in many ways, the “perfect setting” to incubate new pathogens, Spangenberg says, and “an excellent way to transfer diseases from one species to another.” For that reason, many scientists, including Spangenberg, say the world needs, at the very least, to introduce strict regulations for live animal markets.

That’s the message from Elizabeth Maruma Mrema, the United Nations’ biodiversity chief, who has called for a global ban on wildlife markets.

But as Mrema also pointed out, millions of people — particularly in low-income communities — rely on the food and income sources these markets provide.

That’s part of what makes solutions to preventing disease outbreak complex, according to Hayman. Animal exploitation is one part of it, he says. But “poverty, access to jobs, how people are treated in remote areas, the way people engage with food” also contribute to conditions that lead to spillovers.

Read more: 6 things you need to know about the — often shady — wildlife trade

Even just on an economic level, Latinne believes, “we will be forced to change — because the cost of disease emergence and spillover from wildlife will be much higher than the economic benefit of our exploitation of the environment.”

“We are part of nature — we’re part of the ecosystem where our health is linked to the health of wildlife, the health of livestock and the health of the environment,” Latinne says. “We have to find a better way to live together safely.”

Amid coronavirus pandemic, animals reclaiming empty cities

Trip into town

In the coastal Welsh town of Llandudno, usually timid mountain goats have ventured into the empty streets to take a look around. They’ve become an online favorite thanks to Twitter posts by video producer Andrew Stuart. “There’s hardly anyone around to scare them or anything … they just don’t really care and are eating whatever they can,” he said. The UK has been on lockdown since March 23.

Amid coronavirus pandemic, animals reclaiming empty cities

Exploring new ground

In Nara, Japan’s first permanent capital, deer are considered “messengers of the gods” and have been designated national treasures. More than 1,000 regularly wander through the city’s central park, and visitors are encouraged to feed them sugar-free wheat crackers. But with tourists staying away during the outbreak, some curious deer have been quietly investigating nearby shops and restaurants.

Amid coronavirus pandemic, animals reclaiming empty cities

Monkey menace

Thousands of macaques that roam the streets of Lopburi in Thailand haven’t been so polite. Usually well-fed by tourists, the monkeys have been finding snacks hard to come by during the pandemic. They’ve even engaged in intertribal warfare over scraps, fighting in the streets and historic temples. Thailand, the first country outside China to confirm a COVID-19 case, saw 39 million tourists in 2019.

Amid coronavirus pandemic, animals reclaiming empty cities

Urban jungle

This young puma was recently found stalking through the empty streets of downtown Santiago, Chile, followed soon after by two more. The animals live in the nearby Andes Mountains and have increasingly been spotted in the locked down capital, home to about 6 million people. “There’s no people, there’s no noise, so they dare to explore a little more,” said a regional official.

Amid coronavirus pandemic, animals reclaiming empty cities

Unfamiliar territory

India, home to 1.3 billion people — around 17% of the world population — began its ongoing lockdown on March 24. Most flights have been suspended, and these stray dogs have taken advantage of the abandoned arrivals area at the Kolkata airport. There are tens of millions of strays roving the country’s streets and slums; a law has made it illegal to kill or maim the animals.

Amid coronavirus pandemic, animals reclaiming empty cities

Strays rule the streets

Strays are also common in Istanbul — the city on the Bosporus has about 15 million inhabitants, but counts more than 200,000 free roaming cats and dogs. Local authorities regularly provide food and checkups for the animals, and that hasn’t let up during the pandemic. Animal rights activists have said pets are increasingly being abandoned, amid false reports they can pass the virus on to humans.

Amid coronavirus pandemic, animals reclaiming empty cities

Calm canals

Venice, usually a popular tourist destination, has seen dramatic changes during the outbreak which has brought Italy to near collapse. The northern city is normally swamped with visitors, but canals have emptied during the country’s strict lockdown measures. Without the constant passage of boat taxis and gondolas the muddied waters have settled, and seabirds and fish are once again visible.

Amid coronavirus pandemic, animals reclaiming empty cities

Visiting the neighbors

The United States, the new epicenter of the pandemic, has been gradually imposing varying degrees of lockdown measures across the country. In Chicago, the Shedd Aquarium has closed its doors to the public until at least April 30. In the absence of visitors, the center’s rockhopper penguins have been allowed out to explore.

Author: Martin Kuebler