Early Control Would Ease ASF Damage in U.S.

February 3, 2021 — 

Officials predict costs of an outbreak could be reduced to $15 billion from $50 billion if it was controlled within two years. [Source: Western Producer 28 January 2021, by Barb Glen]

African swine fever could become endemic in the United States if it arrives in North America.

Paul Sundberg of the Ames, Iowa-based Swine Health Information Centre said the virus is a looming threat that could cost the American pork industry an estimated $50 billion over 10 years.

Speaking to a recent online session about ASF organized by Swine Innovation Porc, Sundberg estimated an outbreak in the U.S. would cause hog prices to fall by 47 percent in the first year of an outbreak and if it lasted for 10 years, would reduce pork production by almost 30 percent.

But things would be markedly different if an outbreak could be controlled within two years of arrival in U.S. pigs. In that case, prices would be expected to stabilize at base line levels within two years.

And instead of $50 billion in losses over a 10-year period, control within two years would limit losses to $15 billion. If it took 10 years to gain control over an outbreak, he estimated 140,000 job losses in the U.S. alone.

Sundberg said the Swine Health Information Centre is using grant funding for research in Vietnam, where ASF is an issue. By sharing knowledge and analyzing samples, researchers hope to learn more about ASF prevention and how to handle the illness in large hog operations.

"What we're trying to do here is look over the hill and be prepared for ASF as it comes to North America, as it comes to the U.S. and as it gets into the production with the opportunity for it to be endemic," he said.

ASF is a fatal illness in hogs with no available and approved vaccine. It decimated China's hog herd several years ago and has since spread through Asia and Eastern Europe. Infection rates in Germany, Romania, Russia, India, the Philippines and South Africa are rising, according to the World Organization for Animal Health.

"We're going to go on farms in Vietnam and do epi-surveys with outbreak farms to try to identify the probable pathways of entry to help inform us of what we need to look at in the U.S. should we get ASF here," Sundberg said.

American researchers are also examining the options for early detection of infected animals and protocols for their targeted removal.

"If you can identify animals quickly, either individually or group housed and remove them and remove the contact animals, we may be able to stop the infection in its spot and save the rest of the production."

Sundberg said he is watching with interest the work of Canadian Food Inspection Agency researcher Aruna Ambagala on ASF detection. The disease is difficult to identify in its early stages and symptoms might not initially appear to be ASF, Ambagala said.

A system of surveillance would be ideal but individual sampling is labour intensive and costly so he is investigating options for tests of oral fluids from swine. Those are easy to collect by having pigs chew on a rope placed in pens, for example, and then testing the saliva.

Ambagala said early results show ASF can be detected in oral fluids before clinical signs appear in the animals. However, more testing is required to ensure detection is accurate and reliable.

If widespread testing is a viable option, Sundberg identified another challenge to address.

"Should we get ASF, we don't have enough veterinarians to do the job in a biosecure manner to collect the samples that are needed," he said.

A collection training program is now being organized in the U.S. to address that.

However, the primary aim is to keep ASF out of North America entirely.

"We want to make sure that we don't miss something as we address the priorities," said Sundberg. "We want to make sure that we can close all of those windows that we can close to prevent ASF from getting into the U.S."