Hundreds of outbreaks of emerging infectious diseases have been reported in recent decades, and the rate at which they break out is increasing as human activities and encroachment “undermine the integrity of naturally balanced ecosystems”, according to Christian Walzer.
And he warns that future outbreaks of zoonotic disease are inevitable “as the interfaces between wildlife and humans increase, primarily due to deforestation and agricultural expansion”.
Between 1940 and 2004, more than 335 new infectious diseases were recorded – more than 50 outbreaks a decade, with “significant implications for both public health and economic stability”, the peer-reviewed paper says.
Most emerging infectious diseases, including Covid-19, are zoonotic, meaning they pass from wild animals to humans.
“The pragmatic, most cost-effective action governments can take with immediate effect is to ban the commercial trade of wild birds and mammals for consumption,” the document says.
A worldwide ban on trade in wild species for consumption would also benefit local people, it argues. “Most importantly, this reduces the risk of future zoonotic transmission while also safeguarding resources for those indigenous peoples and local communities who rely on wild meat to meet their nutritional requirements.”
The call comes as new analysis of official figures found the US imported almost 23 million whole animals, parts, samples and products made from bats, primates and rodents between 2010 and 2014.
The Center for Biological Diversity discovered that rodents, bats and primates, which harbour most known zoonotic viruses, were traded dead and alive for jewellery, meat, skins, trim and hunting trophies.
The UK also legally imports millions of creatures to be sold as pets, a report earlier this month found. But globally there is much crossover between the legal and illegal trades.
Dr Walzer, who is executive director of health at the US-based Wildlife Conservation Society, writes: “The commercial use of wildlife for consumption encompassing both legal and illegal trade is poorly regulated with porous boundaries between the two entities.
“This trade, particularly in live animals, creates super-interfaces along the food value chain, co-mingling species from many different geographies and habitats while creating perfect conditions for the exchange and recombination of viruses.”
The paper, called Covid-19 and the Curse of Piecemeal Perspectives, published in Frontiers, says the costs of many recent disease outbreaks, such as Sars, Mers and Ebola, were estimated in the tens of billions of US dollars.
In less wealthy countries, the costs of outbreaks exceed 1-2 per cent of GDP, passing the International Monetary Fund's threshold – 0.5 per cent of GDP loss – to count as major economic disasters.
“When all is tallied, it is certain that the economic devastation caused by Covid-19 will be orders of magnitude greater: in the trillions to tens of trillions of US dollars,” it says.
World Health Organisation director-general Tedros Adhanom Ghebreyesus said earlier this year: “Any efforts to make our world safer are doomed to fail unless they address the critical interface between people and pathogens, and the existential threat of climate change.”
Dr Walzer recommends reducing the risk with steps including social marketing campaigns to reduce demand for wildlife as food, and providing alternative protein and micro-nutrient sources.
The paper also warns that focusing on wildlife markets is insufficient to prevent diseases because they are just one part of the supply chain, which includes risky wholesale trader warehouses, stores, transport, wildlife farms, restaurants, pet shops, and border crossing points.
Enforcing hygiene standards and sanitising markets and restaurants that sell wildlife is important but will not prevent outbreaks, it adds.
The Independent has asked Cites, the global agreement on wildlife trade, to comment.