[Accipender]

(2011.Nov.23 07:15 PM)cipher Wrote:  As Dusti's post mentioned, the flu vaccine is made from inactive virus strains.

It can't give you the flu. What it can give you is some of the symptoms of having the flu, and those are caused by your body's immune system responding to the vaccine.

Strictly speaking, this isn't 100% true. They try to make them inactive, but viruses are unpredictable and sometimes (albeit rarely in high-profile diseases such as flus) they contain active strains. Further, generally people experience mild symptoms because the body quickly launches into a defensive mechanism after recognizing the flu.