Add to this chart, the morphing of the human strain, and a carpenter returned from Mexico transferring infection BACK to a little piggie herd in Canada. Go figure?
A/H1N1 Pandemic Alert Special
Maybe, like Shirat Devorah proposes, there is so much more to this flu cocktail? Just how does one explain that 'most' of those coming down with the flu 'only' have typical mild flu symptoms, but there are many, many, many more of them all over the world. Those people who were in Mexico are more susceptable to a positive confirmation of the swine flu.