You also may want to check out a post I wrote about elderberries and the way that the components in this fruit prevent the bacteria and viruses from entering the cells. http://www.foodfreedomrevolution.blogspot.com/2010/09/elder-berry-for-flu.html
I have found that making my own elderberry tincture from dried berries, has been very helpful in preventing flu and colds, when taken at the first sign of illness and/or as a preventative when venturing out to a place where you know you will be exposed. It is also helpful to take it when under stress.
For a very helpful talk on vaccines from the In Short Order Radio Show, check out this episode
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