She was so young too
It doesn't actually say she died from swine flu, and honestly I am rather skeptical that the swine flu is deadly to those of perfectly good health and a young body. Of course it did mention she had previous medical issues before and naturally anyone suffering from any flu would have trouble then. I think we also have to take into account that people want to blow this whole thing up for high publicity and get people panicking, as the article said they were reluctant to comment on her previous bad health, so anyone who dies and technically had swine flu before is going to be an advantage for the press.
Though people have died in Mexico so I could be wrong.