Even though both the classical swine flu and humans seasonal flu H1N1 originate from Spanish flu 1918.

I'm not sure I'm understanding your question. I thought the H1N1 flue going around this year was a newer strain?

Swine flue is able to cause a pandemic as it has mutated(changed) and is now able to infect humans.

Swine flue is a disease that normally just infects pigs, but now it has been transferred to humans making a new version of the HINI type, which is very contageous, even some animals can catch it, all be it rare.

I had swine flue last August and was given a course of Tamiflue, plus kept in isolation for over 2 weeks.

The effects vary from person to person.. the biggest problem I found was the total exhaustion you feel, barley able to put one foot in front of the other.

That feeling to a lesser degree does last for some weeks after.

Lots of people have had it, many were not even aware, the symptoms were so slight,they just thought that they had a bit of a cold.

Wouldn't want it again, although you can get it twice.