China has been reporting some new outbreaks of African swine fever in recent months, but the problem is likely much worse than it appears. That’s both an opportunity for U.S. pork producers and a threat to their herds, according to U.S. industry and government officials.

About a month ago, China notified the World Trade Organization that it had discovered six hogs that contracted ASF, a virus deadly to swine but not a human health risk. Three of the hogs were still alive and three had died.

It was the fourth such notification since the end of January and relatively mild, compared to the massive outbreaks of the disease over the past three years, but U.S. government and industry officials fear the situation is grimmer than the Chinese are letting on.

“There is still a very serious outbreak that continues to occur in China,” says Dave Pyburn, chief veterinarian for the National Pork Board. 

China has been marshalling its forces to restructure its pork sector and clamp down on the virus that resulted in the death of more than half the pigs there, but Pyburn says anecdotal reports from veterinarians working in China suggest the situation hasn’t improved as much as the Chinese government is claiming.

Agriculture Secretary Tom Vilsack told the National Association of Farm Broadcasting in March that he is also suspect of Chinese claims that the virus is under control.

Tom Vilsack

Ag Secretary Tom Vilsack

“I suspect that what we have is a situation where there are probably some hot spots that are taking place in China,” Vilsack said. “They don’t have it totally under control, but I don’t think it’s anywhere near as devastating as it was six or nine months ago.”

But the situation in China is bad enough to seriously delay China’s efforts to expand its herd size, according to a report out of Beijing by USDA’s Foreign Agricultural Service.

ASF is still spreading and new variants of the virus are a major part of the problem, according to USDA and Pyburn.

“In November and December 2020, China experienced a resurgence of ASF,” according to the FAS report. “Chinese veterinary institutes identified new strains of ASF, which due to lower virulence and lethality were able to spread to a larger portion of the herd before being detected.”

These new variants are particularly dangerous to breeding sows, causing lameness as well as increasing the mortality rate of piglets.

Quoting Chinese industry sources, FAS says ASF-related deaths of breeding sows — either from the virus itself or culling — range from 20-50% in different regions. It was only about 10 days ago that China issued a ban on transporting live breeding sows and piglets, a delay helped exacerbate the spread of ASF.

“Now we’re seeing less and less of the first strain of ASF,” Pyburn tells Agri-Pulse. “Now there are more and more variants.”

The proliferation of variant strains of ASF, together with damage still being done by the virus, represents both an opportunity and a threat, says Pyburn. On the one hand, it means Chinese demand for imports remains strong, but it also increases the potential for the virus to make it to the U.S.

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The U.S. exported 239,498 metric tons of pork – valued at about $532 million — to China and Hong Kong in the first quarter of 2021, according to the U.S. Meat Export Federation. That’s a 27% drop from the first quarter of last year, but it’s still enough to make the country the largest foreign market in the world for U.S. exports.

“For us,” Pyburn said about the U.S. pork sector, “what it means is that China is likely to be a buyer of our pork for an extended period of time, but there’s also a downside. … You have the potential for people to come into contact with the virus in China and potentially bring it into this country or other countries.”

International travel remains sparse because of the coronavirus, but that’s expected to change as the world recovers from the pandemic. That adds a whole new wrinkle for the spread of a different virus  — ASF — that is also mutating.

Dave Pyburn

Dave Pyburn, National Pork Board

ASF spread quickly to countries like Vietnam and the Philippines and the further it goes, the more threat it poses to the U.S., says Pyburn.

“We could have outbreaks in other countries that haven’t had one yet,” he stressed. “And then we’ve got even more people in more places where the virus is moving through pigs and that again increases the risk to us here in the U.S.”

While the virus is not known to infect people, people can inadvertently spread it. It’s enough of a threat that the USDA is on high alert.

“Our focus is what we are doing here inside the country to prevent an ASF outbreak,” a spokesman for USDA’s Animal and Plant Health Inspection Service tells Agri-Pulse. “USDA is working closely with other federal and state agencies, the swine industry, and producers to take the necessary actions to protect our nation’s pigs and keep this disease out. This group is also actively preparing to respond if ASF were ever detected in the U.S.”

The impact of an outbreak on the U.S. pork sector would be dire, and National Pork Producers Council CEO Neil Dierks says he’s wary.

“We’re watching it closely,” he said in a recent interview before stressing that China “has a long way to go” before he’ll be convinced the country has the virus in check.

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