From a Slate.com article called "Hand-washing in public bathrooms".
Dry skin tends to crack and flake and may become more permeable to infectious agents.
So if you want to avoid dry skin, and thus avoid getting swine flu, use handcrafted soap. I'm well known for inviting people to touch my soft silky hands. I tell them that not only do I never use lotion, I also have my hands in soapy water a LOT. And my hands are never dry, unless of course I do a lot of dishes!
It is a fact that commercial soap and detergents will dry your skin. And ours doesn't.