China's animal trade to spawn more viral outbreaks: experts

Dan Martin
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A turtle for sale at a market in Wuhan, the epicentre of a deadly new virus that came from an animal

The animal-borne SARS virus 17 years ago was supposed to be a wake-up call about consuming wildlife as food, but scientists say China's latest epidemic indicates that the practice remains widespread and a growing risk to human health.

Like SARS (Severe Acute Respiratory Syndrome), which was traced to bats and civets, the virus that has killed dozens in China and infected almost 2,000 people is believed to have originated in animals trafficked for food.

Final findings are yet to be announced, but Chinese health officials believe it came from wildlife sold illegally at a market in the central city of Wuhan that offered enough animals to fill a zoo, including civets, rats, snakes, giant salamanders and live wolf pups.

The so-called "bushmeat" trade, plus broader human encroachment on wild habitats, is bringing us into ever-closer contact with animal viruses that can spread rapidly in our uber-connected world, said Peter Daszak, president of EcoHealth Alliance, a global NGO focused on infectious disease prevention.

The Global Virome Project, a worldwide effort to increase preparedness for pandemics, which Daszak is a part of, estimates there are 1.7 million undiscovered viruses in wildlife, nearly half of which could be harmful to humans.

Daszak said the project's research indicates we can expect around five new animal-borne pathogens to infect humanity each year.

- 'New normal' -

"The new normal is that pandemics are going to happen more frequently," he said.

"We are making contact with animals that carry these viruses more, and more, and more."

Viruses are a natural part of the environment, and not all are the stuff of sci-fi horror.

But the recent track record of animal-hosted viruses that "jump" to humans is sobering.

Like SARS, which killed hundreds in China and Hong Kong in 2002-03, Ebola also was traced to bats, while HIV has roots in African primates.

Today, more than 60 percent of new emerging human infectious diseases reach us via animals, scientists say.

Even familiar menu items like poultry and cattle -- whose pathogens we have largely adapted to over millennia -- occasionally throw a curveball, like bird flu or mad-cow disease.

"For the sake of these wild species' future, and for human health, we need to reduce consumption of these wild animals," said Diana Bell, a wildlife disease and conservation biologist at University of East Anglia who has studied SARS, Ebola and other pathogens.

"But, 17 years on (from SARS), apparently that hasn't happened."

Wild-meat consumption itself is not necessarily dangerous -- most viruses die once their host is killed.

But pathogens can jump to humans during the capture, transportation, or slaughter of animals, especially if sanitation is poor or protective equipment not used.

With scrutiny rising amid the viral outbreak, China on Sunday ordered a temporary ban on wildlife trading until the viral epidemic eases.

But conservationists say China has repeatedly failed to deliver on pledges to crack down.

Chinese authorities have addressed the problem partly by encouraging a farmed-animal industry.

This has included for endangered species like tigers, whose parts are prized in China and other Asian countries as aphrodisiacs or for other uses.

But that comes with its own downside, by providing a channel for more sought-after wild-caught beasts to be laundered as "farmed," Bell said.

She added that wildlife traders also had become more savvy, avoiding market scrutiny by selling directly to restaurants.

- 'Difficult to stop' -

Environmental groups say Chinese demand, fuelled by rising consumer buying power, is the biggest driver of the global bushmeat trade today.

Some rare species have been prized in China as delicacies or for unproved health benefits since ancient times.

Traditionally, a host gains "face" by serving guests or business partners expensive, hard-to-acquire wild fare.

Yang Zhanqiu, a pathogen biologist at Wuhan University, said modern demand also is bolstered by widespread distrust of a Chinese food industry tarnished by years of repeated safety scandals.

"People will think: wild is natural, natural is safe," Yang said.

"Everyone wants to eat better, so there is a market for wild animals."

Daszak said "it's very difficult to stop an activity with 5,000 years of cultural significance."

But recent surveys strongly indicate that China's younger generation -- swayed partly by animal-rights campaigns involving popular Chinese celebrities -- are much less inclined to tuck into bat, rat, or salamander, he added.

"I think that in 50 years this will be a thing of the past," Daszak said.

"The problem is that we live in such an interconnected world today that any pandemic like this can spread globally in three weeks."