At the heart of COVID-19 is the commercial trade of wild animals in conditions that foster the inter-species transmission of zoonotic diseases. 

Data journalists at Health Analytics Asia analysed over 6 million records of legal trade in wildlife and found that China’s attempts to curb wildlife trade in the aftermath of SARS-CoV in 2003 were short-lived. The volume of  wild animals traded; even legally, has only increased, and popular hosts of zoonotic diseases continue to be traded despite recurring outbreaks of novel zoonotic viruses. 

Will China’s recent ban on wildlife trade and consumption reduce the risk of zoonotic outbreaks? Activists call for global action in curbing wildlife trade as our last chance to avert the next pandemic.

In a remote village in Cameroon, Western Africa; a TV crew follows Patrice and Peti as they forage deep into the forest for nourishment – monkeys, bats, snakes. It is 2008, and this is everyday life for the two hunters who like many other rural, impoverished communities depend on bush meat for sustenance.

Seven thousand miles away, in the city of Tomohon, Indonesia; tourists from across the globe choose from a range of live “exotic” animals slaughtered on-spot by vendors in the city’s bustling wet market.

The hunters in remote Western Africa and the vendors at the populous market in Indonesia have a commonality. They are, often unknowingly; exposed to an emerging public health issue – zoonotic diseases.

Coronaviruses SARS-CoV, MERS-CoV and COVID-19 are all zoonotic diseases whose origins have been traced to wildlife. In March 2020, the Scripps Research Institute concluded from genome sequencing that COVID-19 had natural origins similar to viruses found in bats and pangolins. The origins of SARS-CoV and MERS-CoV have also been traced to bats since their outbreaks in 2003 and 2012 respectively.

While there is scientific consensus that these viruses originate in wild animals, and transmit across species; there is still ongoing research to identify the species of host animals that transmit the virus from a wild animal source to humans. Civet cats, consumed as meat in China have been identified as transmitters of SARS-CoV from bats to humans. Camels, consumed as meat in Saudi Arabia have been identified as transmitters of MERS-CoV from bats to humans. More recently, pangolins, consumed as meat in China have been identified as potential transmitters of COVID-19 from bats to humans.

Doctors and environmentalists unequivocally point to the increase in human-animal contact as a result of deforestation, wildlife trade and consumption, as causes for the recurrence of novel zoonotic viruses.

In an address to journalists on 24 March, renowned virologist Dr Shahid Jameel stated, “When you disturb the ecosystem; when you destroy forests; there is more animal-human contact, and more probability of animal-based diseases. If there is a lesson from COVID-19, it is that we should take care of our eco-system.”

The growing market for live wild animals

Despite the recurrence of zoonotic outbreaks, and scientific evidence pointing to the origins of these diseases in wild animals, efforts to regulate wildlife trade, even in the aftermath of zoonotic epidemics have been temporary and ineffective.

Our analysis of historical data on the legal trade of live wild animals global trade in live wild animals has increased by over 750% since 1987.  Not only has the magnitude of trade increased, but countries also trade in a wider range of species. Over 3,193 species of wild animals are legally traded today.

Our findings are based on data from the CITES Trade database managed by the United Nations Environment Programme, which has every record of international trade involving wildlife species listed in CITES Appendices I, II and III as requiring monitoring to prevent future endangerment. Our analysis is therefore limited to legal trade in wildlife, although there is documented evidence of a large market for the illegal trade of wild animals. Additionally, we restrict our analysis to trade in live wild animals, excluding wild plants and animal derivatives such as meat, bones, skins and bodies. We do so in the context of China’s recent ban on wildlife trade, and the supposed role of wet markets in the transmission of SARS-CoV and COVID-19. Data are reported as of 2017, when the database was last updated.

Zoonotic diseases – an emerging threat to public health

Zoonotic diseases are transmitted from animals to humans through “direct contact or through food, water, and the environment”. They are immanent in our eco-system for as long as human-animal interaction has existed – 60% of all human diseases originate in animals.

The growing consternation, however, stems from altered conditions in our environment including the large-scale commercial trade of wild animals that facilitate cross-species contamination and inter-human transmission.

One such avenue for zoonotic transmissions is a wet wildlife meat market where a wide range of wild species that would typically not interact in the wild are caged together, and handled in unsanitary conditions.

Speaking about the role of wet markets in the spread of COVID-19, Professor Gabriel Matthew Leung, Dean of Medicine at the University of Hong Kong stated, “In wet markets you have animals under stress. Their immune system is down, and therefore during the handling process including the slaughter that’s when the highest risk of jumping from animals to humans would have occurred.”

The World Health Organization currently recognizes 33 zoonotic diseases, some of which have been traced to wild animals.

China’s failure to curb wildlife trade after SARS-CoV

In 2003, when health authorities identified civets as potential hosts in the transmission of SARS-CoV, the Chinese government announced a temporary ban on wildlife trade and culled hordes of civet cats that were popularly sold in wet markets in the province.

Our analysis of  historical trading data shows that the SARS-CoV outbreak did not curb China’s wildlife trade – specifically, its import of live wild animals. Imports declined marginally in the immediate aftermath of the SARS-CoV outbreak, only to increase to unprecedented levels in the following decade.

Today, China remains one of the largest importers of live wild animals.

The path forward

On 25 February, in light of the unprecedented global reach of COVID-19 and calls for action from the World Health Organization, Office International Epizoologie, and the United Nations Environment Programme; the Communist Party of China announced for the first time, a permanent ban on wildlife trade and consumption. The decision was welcomed as long-overdue, but criticism surfaced for its exemption of wildlife trade for medical purposes. Traditional Chinese medicine widely sources wild animals from legal and illegal markets, and has been held responsible for driving wild species to extinction.

Will the ban still reduce the risk of novel zoonotic viruses?

Our analysis shows that China has a large share in the global market for wildlife trade, let alone its sizeable illegal wildlife markets. A permanent ban, therefore, if enforced effectively has the potential to substantially reduce the scale of wildlife trade globally.

Activists say a national ban is not sufficient, and have called for a global ban on wildlife trade.

“If these markets persist, and human consumption of illegal and unregulated wildlife persists, then the public will continue to face heightened risks from emerging new viruses, potentially more lethal and the source of future pandemic spread. These are perfect laboratories for creating opportunities for these viruses to emerge”, Christian Walzer, Executive Director of the Wildlife Conservation Society’s health program told U.S. News.

Despite the availability of research tracing these diseases to wildlife origins, and consensus that exploitation of the environment increases the probability of zoonotic diseases occurring; in a pandemic, the focus shifts to mitigation, leaving the source unaddressed for future prevention.

Zoonotic diseases need to be addressed at their source.