Just a few of the many crazy theories about the origin:

(1) The swine flu was cultured in a lab
(1a) ...as a common enterprise by several governments to fight world overpopulation
(2) The swine flu was started by the Obama government to quicken the process of getting Kathleen Sebelius into office
(3) The flu was started by pharma companies to help increase the sales of flu medications
(4) The flu was a failed attempt to kill Obama when he was in Mexico in April
(5) The flu was started to kill Mexicans so fewer of them come over to the USA.

Those are just a few "theories".

If something bad happens that cannot be controlled and is not understood (completely) then someone just has to be blamed.
When the black death came to Europe many centuries ago the obvious culprits then were, of course, the Jews.
Some centuries later, witches were the first choice culprits for adverse weather phenomena of any kind.

Wolfgang