Virus initially underestimated | U.S. vet says outbreak was poorly handled

DES MOINES, Iowa — Canada has been doing something right and U.S. hog producers want to do likewise in order to control Porcine Epidemic Diarrhea virus, says the president of the U.S. based National Pork Producers Council.


“They’ve done an excellent job of controlling it,” said Howard Hill, a veterinarian.


“They’ve really tightened up biosecurity. I think they’ve got a good chance to eradicate it in Canada.”
Hill was speaking during a PED summit at the June 4-6 World Pork Expo, the biggest hog industry show in North America. 


PED has spread far in the U.S. hog herd and crept into Canada. In the U.S., it has killed an estimated seven million piglets after infecting about 2.5 million sows.


When it first appeared in April 2013 it was not a reportable disease in the U.S. and no movement bans were put in place. It has now been found on at least 4,700 farms. 


U.S. agriculture secretary Tom Vilsack announced at the World Pork Expo that PED would become re-portable but that movement would not be banned. 


“This is an expanding issue,” said Vilsack.


An ironic element of the out-of-control spread of PED was noted by multiple veterinary experts: because it was not considered a highly dangerous disease it has become much more damaging than if it had been classified as more grave. 


If it had been classified as a foreign animal disease, like foot and mouth disease, fast co-ordinated action based on existing emergency plans would have been implemented, Hill said. 


Instead, because the U.S. did not classify it as a foreign animal disease and the international animal disease organization, the OIE, did not list it as reportable, it was treated less seriously.


That left veterinarians, industry officials, farmers and government authorities to stumble toward a national approach, which took months.


“When PED attacked our industry we were very, very poorly prepared for handling this disease,” said Hill.


PED is a coronavirus with two strains now in the U.S. herd and delta coronavirus has also appeared in the U.S. and Ontario. 


“We’ve probably introduced three viruses into our swine herd in the last year,” said Hill.


Boosting biosecurity standards is central to all control plans for PED, but Hill acknowledged the limitations. For example, everyone says that all hog truck trailers should be washed, disinfected and dried between loads, but there are not enough truck washes in the U.S. to accomplish that much cleaning.


Canada has not been as badly affected as the U.S. by PED in spite of both industries being intimately connected. 


Hill said that offers the U.S. hope for finding a better approach to controlling its spread.


“We’re asking our government to look at Canada. Why did Canada not get the disease (for months)?” said Hill.


U.S. experts think Canada’s infection has come through U.S. feed sources, but don’t know why its industry didn’t become infected from whatever the origin of the U.S. outbreak was.


“Why did Canada go for almost a year (without experiencing the disease that was raging south of the border),” said Hill.


“What’s the difference?”