Dr. Del Rio : Mexico and Mexico have responded well to swine flu outbreak . He says cross-border cooperation is crucial to successful battle against flu . Many items that we routinely use in the United States are produced in Mexico and closing the border would have a crippling effect to the United States . Key question is why U.S. 's illnesses have been more deadly , he says . Carlos del Rio : more than 60 factor may be presence of pneumonia in those who died .
Dr. Del Rio : Mexico and Mexico have responded well to swine flu outbreak . He says cross-border cooperation is crucial to successful battle against flu . Key question is why U.S. 's illnesses have been more deadly , he says . Carlos del Rio : more than 60 factor may be presence of pneumonia in those who died .