Steven Galster has been campaigning for years against Asia's illegal wildlife markets where animals are sold live or slaughtered onsite for food – where it's believed the deadly Coronavirus originated.

"We're not surprised because we've been trying to warn people that this is global," Galster told 60 Minutes.

"There are sleeping time bombs across the region right now."

60 Minutes reporter Liam Bartlett on what used to be the busiest market street in Hong Kong. (Nine)

Governments throughout Asia claim they've shut down wildlife markets because of the Coronavirus pandemic.

But 60 Minutes revealed the illegal markets are still running in Bangkok, Thailand, where reporter Liam Bartlett joined Steven Galster undercover to expose the continued trade of live and slaughtered animals.

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At the Chatuchak market in the heart of Bangkok, wild animals smuggled from across the world – including serval cats from Africa, fennec foxes from the Sahara, marmosets from South America and a host of snake, monkey, lizard and tortoise species – are for sale, as captured by 60 Minutes hidden cameras.

The undercover vision is not only confronting to watch but exposes a serious health risk, according to scientists.

Undercover vision at the Chatuchak wet market in Bangkok (Nine)

Liam Bartlett undercover at the Chatuchak market in Thailand. (Nine)

These animals are never together in the wild and so are vulnerable to viruses carried by each other. Their extreme stress, which diminishes their immune systems, adds to the potential of these viruses crossing over to humans zoonotically (across species) during the handling process at markets, including during slaughter.

The Coronavirus is believed to have originated at a wildlife market in China's Wuhan city, in the Hubei province. It is suspected that the virus crossed to humans from the pangolin, the most trafficked wild animal in the world.

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"It's a wild animal that's been taken out of its natural environment, consumed in some way, come into contact with people in an unnatural way," Galster told Liam Bartlett.

"I think the pangolin… who's only defence is to curl up into a ball, has decided that conservationists weren't doing enough, it struck back itself."

"I think this is Mother Nature's revenge."

60 Minutes went undercover at the Chatuchak market in the heart of Bangkok (Nine)

Reporter Liam Bartlett undercover at a Thai wet market. (Nine)

As part of its desperate efforts to contain the virus, China has closed over 20,000 such markets across the country.

But they're still operating with impunity all across Asia, run by organised crime syndicates in Thailand, Indonesia, Laos, Cambodia and Burma.

Steven Galster says to stop the spread of COVID-19 – the illness caused by the coronavirus – or prevent the emergence of similar viruses in the future, the illegal markets need to cease altogether.

"If you want to stop the next pandemic, it's going to have to be truly a global attempt to shut these markets down," Galster told 60 Minutes.

"Coronavirus is spreading all over the world. We need to not just shut down the markets in China, you need to shut them down in other places too. Otherwise it's going to expand or recur."

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