CANADA: Human-to-swine transmission escalates mutation risk
Posted: May 4th, 2009 - 12:12am
News that pigs contracted swine influenza A H1N1 virus from a human on a central Alberta farm should not alarm consumers of pork because the virus is not food-borne, food safety experts say.
But the unusual development creates a whole new series of challenges for public-health officials trying to limit the spread of the new form of flu in humans and swine alike.
“It happened once, it could happen again elsewhere,” said Peter Ben Embarek, a food-safety scientist at the World Health Organization.
As the virus jumps from pigs to humans and back again it risks mutating and becoming more dangerous to both species. And there is an added concern now that swine flu has been reported in parts of Asia where avian influenza is already present, and the pandemic strains could mix into a lethal cocktail.
“That is, of course, a concern and this is why it is necessary to monitor the situation closely,” Dr. Embarek said.
Yesterday, the WHO reported that there have been 937 confirmed cases of H1N1 flu in 18 countries.
Canada, for its part, has tallied 101 cases in seven provinces. Nova Scotia is hardest hit with 33 cases, most of them at King Edgehill school in the town of Windsor. Manitoba because the latest province hit by H1N1, also in a school-age child.