The Ontario Ministry of Agriculture said Thursday the case of porcine epidemic diarrhea virus was discovered in a farm in Middlesex County in the province's southwest.
Ontario's chief veterinarian said lab tests conducted in Guelph, Ont., on Wednesday detected the virus and the samples have been sent to a federal lab in Winnipeg for further testing.
"For all intents and purposes, you can consider it confirmed," Dr. Greg Douglas said in a news conference.
Several pigs at the farm have died from the illness, he said.
The farm is "under control" and its owner is co-operating with officials, Douglas said.
"No pigs will be leaving in the short term," he said.
"We have no concerns... that any products, animals, are leaving the premises and causing any concern or any threat to the Ontario pork industry."
The farm was already following strict biosecurity protocols but experience in other jurisdictions shows the virus is "extremely difficult" to contain and there could be other cases, he said.
The source of the virus isn't yet known.
Douglas said officials suspected "this day would come."
The virus "can be transmitted by anything contaminated by manure," including trucks, trailers and clothing, a group representing Ontario's hog industry warned its members.
Ontario Pork recommends producers keep trucks and truckers off their property until they have been properly washed and disinfected.
Meanwhile, many producers have expressed worry the pathogen could quickly ravage hog farms here once it crossed the border.
Stewart Skinner, a pig farmer in Listowel, Ont., heard the troubling news at a hog farmers' conference in Banff, Alta.
He said producers had hoped Canada would be spared but considered it unlikely in such a highly integrated market.
"There's trucks going back and forth (between Canada and the U.S.) every week. Because of that, it was only a matter of time," he said.
But he said he was encouraged by how quickly officials moved to contain the threat.
"That's a testament to the process that they've put in place," he said.
"As an industry, we didn't stick our head in the sand and say 'This isn't going to come here.' We said, 'This is probably going to happen, what can we do so that we can lower or mitigate the effects to the best of our ability?'"
Part of the challenge of dealing with porcine epidemic diarrhea is that it first appeared in the U.S. just last spring and has already spread to 22 states.
The American Association of Swine Veterinarians has said no one knows how the virus entered the U.S., or exactly how many pigs have died, but it is in the millions.
The Canadian Swine Health Board recently said PED is not a federally reportable disease in Canada, which means there is no single set of protocols to help prevent it from spreading here or to deal with an outbreak.
Instead, provinces and the industry are sharing information and developing plans with the help of the board.
- with files from Allison Jones in Toronto
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