Wet markets: going viral

Concern about cutting down the rain forests is not just a conservationists hobby horse. As more and more trees are cut down for their wood and the land cleared for agricultural use the unplanned consequence is that more an more mobile and traveling humans come in contact with animals for the first time. These animal populations are reservoirs for many viruses, some, like Ebola and AIDS, make their way into new homes, human bodies. The rain forest is no more than an incubation period's travel from major cities.

But this isn't the only way animals and humans are thrown together in intimate and unaccustomed ways. A zoonosis is a human disease of animal origin and most, if not all, of the emerging and re-emerging infectious diseases are zoonoses (including bird flu). In Asia and southeast asia there is another breeding ground, the wet (live animal) market:

Scorpions scamper in bowls, water snakes coil in tanks and cats whine in cramped cages, waiting to be slaughtered, skinned and served for dinner.

Welcome to the Qingping market in the southern Chinese city of Guangzhou, where everything from turtles to insects are sold alongside fowl and freshly caught fish.

[snip]

In a dark shop near the new medicine mall, feces and urine drip like goo through stacked cages of squawking chickens and meowing cats.

"The Qingping market is dirty," said a Guangzhou-born taxi driver, surnamed Mo. "It's dirty because it's old, and the government is unwilling to put up enough money to fix it." (Reuters via ABC News)

In 2003 SARS was traced to civet cats (a raccoon like animal) in southern China's wet markets. They were culled and banned. But even cursory investigation shows they aren't gone:

Although Guangdong authorities culled thousands of civets in January 2004, investigators recently found the animals, as well as badgers and pangolins, on the black market and in Guangdong's "wild flavor" restaurants, where diners hope exotic meats will bring good fortune.

Health inspectors found 14 frozen and one live civet cat, and 22 kilograms of civet cat meat from 18 animals in a sweep of restaurants across the province, the People's Daily newspaper reported earlier this year.

Exotic animal cuisine may be an acquired taste, but it's a taste that's been acquired by a lot of people in southern China:

Keeping clear of wild animals could prove difficult for some locals, who are known for their eclectic palettes.

Among Qingping's cats and chickens were tiger paws, turtles, insects of myriad varieties, and bundled strips of shredded toads -- some food, others medicine.

"You can eat anything with four legs except the dinner table," says one local expression.

More to the point is the dangerous practice of putting all these animal species together, species that live in widely separated ecological niches in nature, and keep them in the most stressful and unsanitary conditions in ways where the spread of a virus is facilitated. And then opening up this seaming cauldron of virus to millions of people who walk among them, touch them, buy them, bring them home, handle them live, dead and raw, cut them open and finally eat them.

Something to think about. Or try not to think about.

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The original origin for SARS has been traced back to Chinese Horseshoe Bats. Somehow, the virus was passed from the Bats into the Civets which then spread it to other animals and people. There is no mention here of using Bat parts and guano in food and medicine which would certainly have very high levels of virus in them.

Yum!

I guess you're right. But I can't help but think that wet markets have been held in China for many centuries. They may have caused problems in the past of course. But they also gave people regular exposure to animal disease over a gradual, long-term period, probably creating low-level immunities (eg Jenner's milkmaids who didn't contract small pox.) Maybe wet markets aren't what we should be worrying about.

The current trend of "Wild Flavor" is relatively new in China. It is true they do eat a wider variety of things than most western or European countries, but "Wild Flavor" is a totally different phenomena. They can now transport wild creatures from farther away far more quickly than ever.

By G in INdiana (not verified) on 12 Dec 2007 #permalink