Pigs in Canada may be first in recent outbreak to test positive for virus . The U.S. Centers for Disease Control and Prevention said it is investigating a case of swine flu that has been confirmed among pigs at the University of Wisconsin in Madison. Mexico has the most confirmed swine flu cases , with 506 infected people and 16 deaths , the WHO said . WHO reports 787 confirmed cases of H1N1 virus in 17 countries .
Pigs in Canada may be first in recent outbreak to test positive for virus . The U.S. Centers for Disease Control and Prevention said it is investigating a case of swine flu that has been confirmed among pigs at the University of Wisconsin in Madison. WHO reports 787 confirmed cases of H1N1 virus in 17 countries .