NYT: Pig Virus Hits China -- to hit Taiwan?

Last week the NY Times is reporting on a mysterious virus decimating pig populations in China....

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Virus Spreading Alarm and Deadly Pig Disease in China
By DAVID BARBOZA


CHENGDU, China, Aug. 9 — A highly infectious swine virus is sweeping China's pig population, driving up pork prices and creating fears of a global pandemic among domesticated pigs.

Animal virus experts say Chinese authorities are playing down the gravity and spread of the disease.

So far, the mysterious virus — believed to cause an unusually deadly form of an infection known as blue-ear pig disease — has spread to 25 of this country's 33 provinces and regions, prompting a pork shortage and the strongest inflation in China in a decade.

More than that, China's past lack of transparency — particularly over what became the SARS epidemic — has created global concern.

"They haven't really explained what this virus is," says Federico A. Zuckermann, a professor of immunology at the University of Illinois College of Veterinary Medicine. "This is like SARS. They haven't sent samples to any international body. This is really irresponsible of China. This thing could get out and affect everyone."

There are no clear indications that blue-ear disease — if that is what this disease is — poses a threat to human health.

Though the Chinese government acknowledges that the current virus has devastated pig stocks in coastal and southern areas, it has not admitted what experts say is clear: the virus is rapidly moving inland and westward, to areas such as this one in Sichuan Province, China's largest pork-producing region.

"This disease is like a wind that swept in and passed from village to village," said Ding Shurong, a 45-year-old farmer in a village near here who lost two-thirds of his pigs . "I've never seen anything like it. No family was left untouched."

No one knows for sure how many of this country's 500 million pigs have been infected. The government says officially that about 165,000 pigs have contracted the virus this year. But in a country that, on average, loses 25 million pigs a year to disease, few believe the figures. In part, the skepticism comes from the fact that pork prices have skyrocketed 85 percent in the last year — an increase that, absent other factors, suggests the losses from disease are more widespread than Beijing admits.

And there are other signs. Field experts are reporting widespread disease outbreaks. Fear among pig farmers that their livestock will contract the disease has led to panic selling. And the government and media here have issued alarming reports that farmers are selling diseased or infected pigs to illegal slaughterhouses, which could pose food safety problems.

International health experts are already calling this one of the worst disease outbreaks ever to hit Asia's livestock industry, and they fear the fast-mutating pathogens could spread to neighboring countries, igniting a worldwide epidemic that could affect pork supplies everywhere.

A similar virus has already been detected in neighboring Vietnam and Myanmar, and health experts are trying to determine if it came from China.

Health experts say China has declined to send tissue samples to testing labs outside the country for independent verification by a lab affiliated with the World Organization for Animal Health in Paris.

The Chinese government says that it has reported the disease to international health bodies and insists that the disease is under control and that a vaccine has been developed and distributed.

But, some scientists say there is no truly effective vaccine against blue-ear pig disease (which is also known as porcine reproductive and respiratory syndrome); other experts say they are not even certain that the blue-ear virus is the one that is spreading.

Scientists who track blue-ear pig disease are puzzled because the disease is generally not so deadly.

"This virus generally makes them ill but on its own it doesn't cause a lot of deaths," said Steven McOrist, a professor of pig medicines at the University of Nottingham in England. "The evidence they put up so far is not conclusive."

If it is blue-ear pig disease, which has infected most parts of the world, including the United States, it may be a new and more virulent strain.

"This is more severe than we've seen elsewhere," said Derek Armstrong, a senior veterinary scientist at the Meat and Livestock Commission in Britain. "It may be a co-infection of pigs with other things."

The United Nations Food and Agriculture Organization is now pressing China to share its research and tissue samples.

"I've asked my two vets in Beijing to work with the government and get some of those samples out," said Juan Lubroth, head of infectious disease at the F.A.O., noting that China has reported its own findings on the disease. "Our experience has shown us that working with carrots is better than working with sticks."

Government scientists themselves said that last year the virus affected two millions pigs and killed 400,000. Here in Sichuan province, home to some 55 million pigs and one of the world's most densely populated pig breeding areas, there is devastation. Many pig farmers say that what appears to be the blue-ear virus swept through this region in June and July, killing thousands of pigs.

"First they refused to eat, then they got high fever," said Zhao Yanjun, 32, who lost all but 5 of his 150 pigs, just months after building a modern barn in Heishi village, about an hour's drive southwest of Chengdu. "Now, there's nothing left."

Liu Minghong, a 38-year-old farmer, said, "Most of my pigs got hit in June and July — 70 of them died." sitting in a dusty house on the edge of his property, He pulled out a notepad that cataloged the demise of his pigs.

"I sold a lot out of panic," he says.

Pig farmers who did not sell watched their pigs succumb to a disease that ate away at their insides in a matter of weeks, often turning the pig's ear blue. In Mr. Liu's barn, he pointed to one pig that was little more than a skeleton, shivering in a corner, struggling for life.

Now, slaughterhouses here go wanting.

"Last year we slaughtered 1,000 pigs a day; now we're doing 100," said Yuan Zi, a manager at the Qiyuan Meal slaughterhouse near the city of Qionglai. "We've laid off nearly half the staff."

Officials in Beijing worry that widespread pork shortages and soaring food prices could prompt panic, unrest or inflation, undermining a sizzling economy.

Trying to contain the damage, the government has announced a series of emergency measures, offering aid, incentives and free vaccines to farmers.

But the government has also warned against price gouging, and vowed to crack down on farmers selling diseased pigs, or injecting a pig with water to bolster its selling weight.

Still, many here say the problem is that pigs are simply in short supply, and it may take months if not a year or two to restock supplies, assuming the disease does not linger, as some scientists say it generally does.

Many experts, meanwhile, worry that China, which the F.A.O. says is the fourth-largest exporter of live and slaughtered hogs, could already be exporting the disease.

"This is already considered to be a threat to the global industry," said Trevor Drew, head of virology at the Veterinary Laboratories Agency in Weybridge, in southeast England. "It would be naïve to think we could contain this virus."

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In 1997 Taiwan's pork industry was devastated by foot and mouth disease.

Between March and July 1997, a devastating outbreak of foot-and-mouth disease (FMD), serotype O, occurred in pigs in Taiwan. A total of 6147 pig farms with more than 4 million pigs were infected, and 37·7 per cent of the pigs in Taiwan either died (0·18 million pigs) or were killed (3·85 million pigs). The epidemic reached its peak during the fifth week after it was first recognised. During the eighth and ninth weeks, a two-dose blanket vaccination programme was instituted which led to a large reduction in new outbreaks. Except for two cities, the whole of Taiwan was declared an FMD-infected zone. During the four months in which new farm outbreaks occurred, 21·7 per cent of the pigs on infected farms showed clinical signs, and there was an overall mortality of 3·95 per cent. During the early stages of the epidemic, the incubation period was as short as 24 hours and the case fatality rates for suckling piglets reached 100 per cent. The financial cost of the epidemic was estimated at US$ 378·6 million, including indemnities, vaccines, carcase disposal plus environmental protection, miscellaneous expenses, and loss of market value. Owing to the ban on exports of pork to Japan, it is estimated that the total economic cost to Taiwan's pig industry will be about US$ 1·6 billion.

The industry was a big export earner for the island, with large markets in Japan. It never fully recovered. This site has more on it:

On March 19, 1997, a sow at a farm in Hsinchu was diagnosed with a strain of FMD that infected swine only. The cause of this outbreak remains unknown, however, the farm was located near a port city with a thriving pig smuggling industry and illegal slaughterhouses. It is likely that the FMD was introduced through contaminated meat scraps or introduction of smuggled swine into the herd.

Once the index case was diagnosed, the disease spread rapidly through the swine herds in Taiwan. There are several reasons why the disease spread so rapidly:

hog farms close to slaughterhouses

frequent social farm visits

incomplete diagnostic laboratory capability

no vaccination program

In addition to these problems, swine vesicular disease (SVD) was endemic to Taiwan. The clinical signs of this disease are virtually indistinguishable from FMD. To further complicate matters, laboratory analysis was often not employed to diagnose SVD. Therefore, it is likely that several reported cases of SVD were actually FMD. Also, once FMD was confirmed, there was considerable delay between diagnosis and the implementation of depopulation and disposal. Finally, the indemnity payments offered to farmers for swine infected with FMD were often more than the market value of the pig leading many farmers to intentionally introduce FMD onto their farms.

These factors contributed to the rapid spread of FMD across Taiwan and the destruction of over 3.8 million swine at an estimated cost of US $6.9 billion. Prior to this outbreak, Taiwan had been the leading exporter of pork to Japan. The disease devastated the Taiwanese pig industry and eliminated the export market.

Many of these same factors are at play in China as well. How China handles this will be another test of its willingness to be a responsible member of the world community. And given the high level of smuggling between China and Taiwan, look for this disease to make its way here sooner or later.

[Taiwan] [US] [China]