There are 51 pork operations dealing with porcine epidemic diarrhea, up from about 40 at the end of last month, said Andrew Dickson, general manager of the Manitoba Pork Council.
"It caught us off-guard," Dickson said Monday. "We had a total of 10 cases in three years, so that's what's throwing us off for a loop ... What happened this year that we've suddenly got 50?"
He said the virus has so far been contained to about a half-hour's drive radius surrounding Steinbach, southeast of Winnipeg, and farmers are doing what they can — including reviewing biosecurity measures, equipment and clothing — to stop it from spreading.
Although it doesn't pose a threat to human health or food, porcine epidemic diarrhea is almost always fatal for pigs under three weeks of age due to dehydration.
Dickson said trucks that ship swine to the U.S. used to have to be cleaned in Manitoba, where he says the process is more thorough than it is south of the border. But that requirement has been lifted, and he believes that may be a possible cause behind the outbreak.
"I'm not going to say it's caused all of them, but it doesn't help knowing that some of these trailers may be coming back not clean, or been infected," he said.
Dickson said he has called on the federal government to put the requirement back in place and is hopeful it's listening.
The Canadian Food Inspection Agency didn't immediately respond to a request for comment.
The province and industry have set up buffer zones around the affected farms and created a disease management group to share information and co-ordinate efforts.
According to the Canadian Food Inspection Agency, the first confirmed case of the virus in Canada was in January 2014, in Ontario, just as an outbreak swept through the U.S., killing more than eight million piglets.
Since then, the virus has also been reported in Quebec and Prince Edward Island.
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