"A worker at (a Canadian) farm had traveled to Mexico, fallen ill there and unknowingly brought the disease back to Canada last month. The worker has recovered.
About 10 percent of the 2,200 pigs on the farm got sick. According to the Canadian Food Inspection Agency, all recovered without treatment in five days.
The entire herd remains under quarantine as a precaution. New York Times"
For additional information read this Wall Street Journal post titled,
Pigs in Canada Contract Flu Virus