A new analysis is casting doubt on the effectiveness of that annual ritual.
Researchers from the University of Minnesota looked at all of the flu vaccine studies over the past 44 years. They found that the flu shot in adults -- 18 to 65 -- is only 60 percent effective.
Researchers also found the flu mist vaccine -- the nasal mist -- works well for children. It is 80 percent effective in children under the age of 7.
Experts are now calling for a new generation of flu vaccines.