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Virus strikes China's pigs, stirring fears of global outbreak

A worker injected a piglet with vaccine at a farm in Changzhi, China, earlier this month. A mysterious swine virus has spread to 25 of the country's 33 provinces and regions. A worker injected a piglet with vaccine at a farm in Changzhi, China, earlier this month. A mysterious swine virus has spread to 25 of the country's 33 provinces and regions. (Reuters)

CHENGDU, China -- A highly infectious swine virus is sweeping China's pig population, driving up pork prices and spawning fears of a global pandemic among domesticated pigs. And animal virus specialists say Chinese authorities are downplaying the gravity and spread of the disease and refusing to cooperate with international scientists.

So far, the mysterious virus -- believed to be 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.

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," said 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 decimated pig stocks in coastal and southern areas, it has not admitted what specialists assert: The virus is rapidly moving inland and westward, to areas like 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 who lost two-thirds of his pigs in a village near here. "I've never seen anything like it. No family was left untouched."

No one knows for sure how many of China'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 past year -- an increase that, absent other factors, suggests the losses from disease are more widespread than Beijing acknowledges.

Field specialists are reporting widespread disease outbreaks. Fear among pig farmers that their livestock will contract the disease has triggered panic selling. And the government and media here have issued reports that farmers are selling diseased or infected pigs to illegal slaughterhouses, which could pose food safety problems. International health specialists are already calling this one of the worst disease outbreaks ever to hit Asia's livestock industry, and they fear that the rapidly 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 Burma, and health specialists are trying to determine whether it came from China.

The Chinese government says it has reported the disease to international health bodies and insists 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 specialists say they are not even certain the virus gripping China is blue ear pig disease.

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.

The Ministry of Agriculture declined to comment on what areas are most affected.

Officials in Beijing worry that massive pork shortages and soaring food prices could prompt panic, unrest or spiraling inflation, undermining a sizzling economy in, what is, in the Chinese calendar, the Year of the Pig.