How environmental destruction increases the risk of pandemics

By markontour, March 29, 2020

“We disrupt eco-systems, and we shake viruses loose from their natural hosts. When that happens, they need a new host. Often, we are it.” So argues David Quammen in We Made the Coronavirus Epidemic (New York Times, 28 January). There have been a number of similar articles pointing out the link between human destruction of biodiversity and the prevalence of viruses that cross the barrier between animals and humans. Here I summarise those that I have found most useful.

John Vidal (Tip of the iceberg: is our destruction of nature responsible for Covid-19?, Guardian 18 March) argues that human destruction of biodiversity creates the conditions for new viruses by reducing natural barriers between host animals and humans.

Sonia Shah, author of ‘Pandemic: Tracking Contagion from Cholera to Ebola and Beyond‘ concurs and points out that Covid-19 is far from unique (Think Exotic Animals Are to Blame for the Coronavirus? Think Again, The Nation, 18 February 2020). Hundreds of microbial pathogens have emerged in the last 70 years, mostly originating in wildlife. “The problem is the way that cutting down forests and expanding towns, cities, and industrial activities creates pathways for animal microbes to adapt to the human body..A study in 12 countries found that mosquito species that carry human pathogens are twice as common in deforested areas compared to intact forests.”

Pathogens don’t solely originate in wildlife, according to Shah: “many more are reared in factory farms, where hundreds of thousands of individuals await slaughter, packed closely together, providing microbes lush opportunities to turn into deadly pathogens.”

As David Quammen points out, if we want to halt the growing risk from pandemics then we need to stop polluting and destroying the natural world. Covid-19, he argues, is “no novel event. It’s part of a sequence of related contingencies [including SARS and MERS] that stretches back into the past and will stretch forward into the future, as long as current circumstances persist.”

Brian Bird, a research virologist at the University of California concurs: “We can’t predict where the next pandemic will come from. The certain thing is that the next one will certainly come” (quoted by John Vidal, ibid).

Peter Daszak, a disease ecologist, warns that it would be complacent to assume that we will learn to cope with pathogens. “We treat pandemics as a disaster-response issue: we wait for them to happen and hope a vaccine or drug can be developed quickly in their aftermath. But even as Covid-19 rages, there is still no vaccine available for the SARS virus of 2002-3, nor for HIV/AIDS, or Zika or a host of emerging pathogens.” (We Knew Disease X Was Coming. It’s Here‘, New York Times, 27 February)

All that points to the need to strengthen environmental protection and reduce destructive resource extraction. There are plenty of people doing just that and, as John Vidal explains, “a new discipline, planetary health, is emerging that focuses on the increasingly visible connections between the wellbeing of humans, other living things and entire ecosystems.”

Most of these people are not in power, however, while the elected leader of the most powerful democracy on Earth, Donald Trump, is systematically ignoring scientific advice, including using the Covid-19 crisis to suspend enforcement of health and environmental regulations (Citing coronavirus, EPA suspends enforcement of environmental laws, Los Angeles Times, 27 March). As Gina McCarthy, a former Obama-era Environmental Protection Agency chief put it: “No one has ever seen anything like this. This is a complete pass for every industry.”

That doesn’t bode well for the risk of another pandemic. Writing even before the latest Presidential decisions, Sonia Shah warned that “[t]he Trump administration’s liberation of extractive industries and industrial development from environmental and other regulatory constraints can be expected to accelerate the habitat destruction that brings animal microbes into human bodies.”