"I think we need to face reality here. Coronavirus pandemics are not a once in a hundred year event. The next one could come at any time. It could come in 50 years or in 10 years. Or it could be next year."
Pangolin
With a year of hindsight, we all know more about the causes of the
COVID-19 pandemic and zoonotic diseases in general. The nodes of
human-animal connection where coronaviruses jump species are many,
including dogs, cats, birds, chickens, pigs and rodents. But in the
research that has arisen this year, the primary touchpoint is
between humans and wild animals.
Finding the origin of SARS-CoV-2 is crucial for fighting future
zoonotic epidemics, creating drugs for treatments, and developing
vaccines. As noted by Jeremy Rossman in an April 2021 piece in
ScienceFocus, “There are good reasons to look for the origins of the
SARS-CoV-2 virus, although they may not directly affect our current
situation or our ability to control the pandemic. If we’re able to
discover the origins of the virus we may learn if there’s an unknown
reservoir of the virus in some wild animal population that may pose
risks of future SARS-CoV-2 outbreaks.”
Scientists now understand that this pandemic originated in bats,
although here speculation diverges. It is possible that this
coronavirus passed directly from horseshoe bats to humans, or that
it passed through an intermediary host where it further evolved
before jumping to humans. That intermediary host is thought to be
the pangolin. According to an August, 2020 article in The New
Yorker, in 2019 necropsies on pangolins with respiratory distress
who were seized by customs police showed evidence of two viruses:
One harmless to humans and one a coronavirus. Later, as researchers
scrambled to find the source of the COVID-19 pandemic, Chinese
researchers found that although the match overall was not that
close, lung tissue from these pangolins did contain some gene
segments that were 99% similar to parts of the SARS-CoV-2 that
caused this pandemic. Knowing this led to suppositions that that
viral genes were shuffled between bat and pangolin before reaching
humans.
All eight species of pangolin are being pushed toward extinction due
to human consumption of their bodies and trafficking of their skins
and scales. Between 1975 and 2000—when their export was deemed
illegal—approximately 776,000 pangolins became merchandise that was
traded legally on the international market. Up to that point, the
pangolin scales were primarily used in traditional Chinese medicines
(that are not supported by science), while most of the skins went to
North America to be manufactured into fashion accessories like
belts, handbags and boots. As the Asian populations were depleted,
pangolins from Africa that had been regionally consumed as a
bush-meat market commodity supplied an international trade for the
skins, scales and bodies of these docile animals. By 2016 the
situation was so dire that all international trade of wild-caught
pangolins and their parts was declared illegal. That has not stopped
the lucrative trade.
The meek pangolin certainly is not the only species imperiled by the
wildlife trade even in protected areas, according to a recent online
article in Science. Wildlife trafficking impacts tens of millions of
individual animals, generates between $5 and $20 billion per year,
and supports 150 million human families who eat or sell those
animals for their livelihoods. A recent review study of 32 papers
found that in unprotected areas, trafficked species populations
declined by 65% with a less, but still significant, decline of 39%
in areas that were protected.
It is unclear from which animal of these animals the next pandemic
might crossover to humans. (For instance, the 2012 outbreak of
Middle East Respiratory Syndrome (MERS), also a coronavirus, had
established itself in camels before spilling over to humans with the
help of bats.) But it is safe to say that the wildlife trade offers
significant chances for this type of spillover to happen by creating
more instances of wild animal-human interaction at a number of
levels.
As noted in an NPR piece, "We live in a kind of coronavirus world,"
said virologist Edward Holmes at the University of Sydney. According
to Holmes, "We're only just starting to scratch the surface. The
virusphere of coronaviruses is just immense." One research study
from 2018 by the EcoHealth Alliance, found 3% of people tested in
southern Chinese villages had been infected with an unknown
coronavirus within the past few years. His research leads Holmes to
caution, "I think we need to face reality here. Coronavirus
pandemics are not a once in a hundred year event. The next one could
come at any time. It could come in 50 years or in 10 years. Or it
could be next year."
Both the search for the origins of this zoonotic pandemic and
preventing the next one has implications not only for creating a
safer world for humans, but also for the lives and livelihoods of
the wild animals trafficked for human purposes. The general public
now has a much greater awareness that human-animal connections
fostered this pandemic, a global disaster that has taken more than a
year of our collective effort to begin to overcome. With that
knowledge comes an obligation to do what we can not only to prevent
the next pandemic, but also to find solutions that reduce and
ultimately stop the destruction of wildlife species with whom we
share this—our shared and only—planet.