If you google flu and vitamin D, there are many articles/studies about the effect vitamin D has on flu prevention or at least lessening the symptoms. One study shows that the children who have died from H1N1 are severely D deficient.

I have not decided yet about the seasonal flu shot, but will not take the H1N1 shot. Too many unanswered questions for me. I am upping my vitamin D supplements and trying to spend at least 15 minutes in the sun daily. One thing I'm being told by people who had H1N1 and recovered... stay well hydrated. It helps you cough up the gunky junk that seems to develop very quickly with this virus. One lady told me she sat up with her 15 yr old and made her drink fluids every hour for the 48 hours she had the high fever. My brother did the same with my 9 yr old niece. Both recovered within 5 days and were back in school on the 6th day after the high fever started.