The confidence that existed only a few weeks ago about keeping North America free of the highly contagious African Swine Fever may not be holding up.

African Swine Fever (ASF) is a highly contagious and deadly viral disease that threatens both domestic and wild pigs of all ages. Human health is not at risk from the virus, and it is not a food safety issue.

But it’s not very comforting as could kill one out of every four pigs on the planet.

Cooper Farms veterinarian Don Davidson thinks it is likely that AFS is already present in North America. “It’s probably here already: it just hasn’t made its way to a pig yet,” Davidson told this week’s Agriculture & Policy Outlook Conference at Ohio State University.

As recently as last August, the chief veterinary officers of the United States, Canada, and Mexico adopted a common strategy for keeping AFS out of North America. Their plan calls for stepped-up surveillance and “surge capacity” to deliver resources to any location on the continent.

Long associated with Saharan Africa, the virus this time reached China, Mongolia, and Vietnam before entering other areas of Europe and Asia.

More than live domestic and wild pigs can spread ASF. The virus can e transmitted on clothing and equipment and feed and international travelers. “We might be our own worst enemy, ” Davidson, a port supply chain expert, told the OSU internationally transmitted conference.

The World Organization for Animal Health, which tracks the outbreak in detail, now predicts 25 percent of the world’s pigs will ultimately be wiped out by the ASF. Another part of the North American strategy is upping biosecurity measures to address every pathway that might spread the virus.

In its latest “Global Situation” report, OIE said Europe accounts for most of the outbreaks, but most of the animal losses are occurring in Asia.

Asia has lost more than 1.8 million pigs, while Europe’s losses were about 1 million. Most were domestic pigs, followed by about 300 cases of wild boars.

Worldwide, ASF has taken more than 2.9 million animals since 2016. Since that date, OIE says there’s been a significant increase in the frequency of outbreaks.

The virus can survive in pork products for months. Specially trained dogs are being used by the Customs & Border Patrol to help USDA snift out pork contaminated with the virus. Davidson says companies may not be giving workers enough downtime between assignments on different farms, including those in different countries.

The North American strategy also demands to report sick pigs. While not a danger to humans, ASF symptoms are dramatic and aren’t likely to be missed. They include high fever, loss of appetite, depression, weakness, red, blotchy skin or skin lesions, vomiting, diarrhea, coughing or difficulty breathing, abortions, and sudden death.

USDA says if ASF does reach the USA, it will have a “significant impact on U.S. livestock producers, their communities, and the economy.” There is no vaccine or treatment for the virus, only death.

As of March 1, there were 74.3 million hogs and pigs on U.S. farms, up 2 percent from March 2018, but down slightly from December 1, 2018, according to the Quarterly Hogs and Pigs report published  by the USDA’s National Agricultural Statistics Service (NASS).

About one billion domestic pigs exist worldwide, more than any other animal.

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