According to the Ministry of Agriculture, Fisheries and Food of Quebec (MAPAQ), the 2009 H1N1 influenza virus infected a herd of pigs in this Canadian province. This is only the third hog farm known to have become infected with the virus that is causing the swine flu pandemic in humans. A statement says a federal laboratory in Winnipeg identified the virus on 24 July.
An earlier infection of a Canadian pig herd in Alberta received intense attention because of the possibility that the virus isolated from the animals might help clear up questions about the origin of the pandemic. Genetic analyses of the human viruses could not find any close match with viruses currently circulating in pigs, suggesting that an ancestor of the 2009 H1N1 may have circulated in swine or other species undetected for many years. The Canadian Food Inspection Agency (CFIA) dismissed the idea that the Alberta pigs infected humans, insisting from the outset that it was “highly probable” that it was the other way around. But the genetic evidence has been confusing.
A CFIA spokesperson told ScienceInsider that it could not immediately address questions about the genetic sequence of the virus in the Quebec herd. Canadian media reports quote officials from MAPAQ saying this infection, too, likely is a case of the virus moving from humans to pigs, but there is no evidence of any humans with the disease interacting with the herd.