There is an old Chinese proverb that says even the longest journey begins with a single step. Likewise, the odyssey of humanity through the COVID-19 pandemic had its origin in a simple step that we may never learn about in detail; at some point, somewhere, a single contact of a human with another animal caused the first infection of the coronavirus SARS-CoV-2. Fortunately, this happens very rarely; a recent study estimates that the virus circulated among bats for 50 to 60 years before accidentally infecting the first human. But it is also rare for a large killer asteroid to impact the Earth, and yet this has happened in the past, and animal viruses are just as abundant as space rocks; speaking only of coronaviruses and only of Chinese bats, one study found a total of 781 of the former in the latter. Today many researchers are working not to stop the current pandemic, but to prevent future ones, with one question in mind: how should our relationship with animals change so that this never happens again?
SARS-CoV-2 is by no means the only zoonotic virus —jumping to humans from other animals— which we have discovered in recent decades. From HIV, whose outbreak came from non-human primates, to the SARS and MERS coronaviruses, which originated in bats but spread to humans from civets and dromedaries, respectively, to Ebola (bats and primates) or influenzas such as H5N1 (birds) or the H1N1 pandemic of 2009 (pigs), we have had more than enough serious warnings in recent times. In fact, 60% of emerging infectious diseases (EID) are zoonotic, and over 70% of these originate in wild animals.
In the case of the new coronavirus, it has not yet been possible to ascertain precisely how that fateful leap occurred, though it may not have happened in the Wuhan seafood market as initially believed. But whether it did or not, there is no doubt that certain establishments where different animal species of dubious origin are concentrated under unsanitary conditions are a recipe for disaster. That was the origin of the SARS coronavirus; and pangolin, an animal possibly involved in the evolution of SARS-CoV-2, is sold today in some Asian markets as a culinary delight and as a source of ingredients for Traditional Chinese Medicine (TCM).
Restrictions on the wildlife trade
Both the taste for exotic and expensive species and TCM are major forces buoying the wildlife trade. Since the beginning of the pandemic, voices have been raised in China and elsewhere calling for restrictions on this trade. On 24 January, when confinements in China were spreading and the world did not yet appreciate the full extent of the coronavirus outbreak, conservation biologist Diana Bell of the University of East Anglia, who had already studied the case of civets and SARS, wrote: “We have to hope that the Wuhan outbreak is a wake-up call for regulation of wildlife trade and animal health, action that is urgently needed to protect human health and the environment.”
Chinese authorities reacted promptly by temporarily suspending trade in wild animals, and on February 24 the Chinese Congress passed new legislation restricting the consumption of these species. In the journal Science, two groups of Chinese researchers and academics published articles calling for a total ban: “China must act to permanently ban wildlife consumption in order to prevent future public health risks,” said one of the articles. In the authors’ view, the measures taken left significant gaps; for example, the medicinal use of wildlife products was not covered by the ban. Chinese President Xi Jinping himself is a staunch supporter of TCM and has promoted its use against COVID-19. On the other hand, added one of the articles, the fact that some wild species are legally farmed offers a route to the black market “laundering” of wild animals.
But even with the baby steps happening in China, including the removal of pangolin from the TCM pharmacopoeia, the capture of wild species for consumption is a global problem. Because of this and the spread of the pandemic, more than 300 conservation organizations have signed a letter asking the World Health Organization (WHO) to call on governments to close the markets and the trafficking of wildlife. According to Simon Evans, an ecotourism specialist from Anglia Ruskin University, “most conservationists continue to favour blanket trade bans.”
Others, however, argue that it is not that simple. According to Alex Bowmer of the London School of Hygiene & Tropical Medicine, a large-scale ban “could hinder rather than help the prevention of further pandemics.” Bowmer points out that not only do wildlife products have a cultural value in many countries that sustains demand, but bushmeat is a primary source of food for countless households, so outlawing it would encourage a black market, something that has already occurred; the banning of bushmeat in West Africa after the Ebola outbreak in 2013 boosted the illegal trade. These habits are difficult to change, experts warn, and are not achieved through bans. “A more appropriate response would be to improve wildlife trade regulation with a direct focus on human health,” wrote a group of scientists from Oxford University.
The disruption of ecosystems, another threat to biosecurity
Nor does the risk of future pandemics of zoonotic origin lie solely in the wildlife trade. Deforestation, land use conversion and the encroachment and urbanization of natural areas are all threats to biosecurity, as the disruption of ecosystems facilitates contact between different species and between these and humans. As a new and extensive study in Nature shows, the loss of biodiversity encourages the expansion of generalist species with high zoonotic potential, such as rats, mice and bats. The United Nations has warned that environmental degradation explains the increase in zoonosis over the last century, and that the replacement of natural areas with farmland turns livestock species into epidemiological bridges to humans; one example is avian flu, which jumped from wild birds to farmed chickens and from these to humans. The worrying increase of a type of influenza in pigs that the authors of the study describe as “a candidate for a pandemic virus” has been described in China.
All of the above points to a conclusion that the scientific and academic community has been repeating for years, but which perhaps has not yet permeated deeply enough into the public’s vision, in which disinformation favours the acceptance of simplistic and fanciful explanations —such as conspiracy theories— regarding the current pandemic: environmental degradation, including the effects of climate change, is not an exclusively ecological problem, but one that has catastrophic consequences for our health and safety. “Collaborations, such as between health law and conservation law, must be put in place,” stresses lawyer Katie Woolaston from the Queensland University of Technology. “For example, while the WHO works on zoonosis prevention, there is little interaction between it and the Convention on the International Trade of Endangered Species [CITES].”
With regard to what should change in the wake of this pandemic, there do seem to be some obvious gaps that need to be filled urgently: “To date there are no international or national conventions on pathogen screening associated with animals, animal products, or their movements, and capacity for emerging infectious disease diagnostics is limited along much of the human-wildlife interface,” writes a group of experts from the Wildlife Disease Surveillance Focus Group in Science. “EID risks associated with the wildlife trade remain the largest unmet challenge of current disease surveillance efforts.”
In terms of stopping habitat destruction and restructuring our relationship with nature, this may seem an enormously complex task, hampered both by inertia and the economic interests involved. But as another group of experts pointed out in Science, “we currently invest little in preventing deforestation and regulating the wildlife trade […] The costs associated with these prevention efforts would be substantially lower than the economic and mortality costs of responding to these pathogens once they have emerged“. This can be summed up in another old saying: an ounce of prevention is better than a pound of cure, because it will also cost us less.