answer:Flu shots on good years are around 60% effective, as in 40% of people who get them are still capable of catching the flu. Unfortunately the Flu mutates so quickly that a lot of times the vaccine we work up is for an older version of the flu by the time we start giving it out in shot form. I didn’t get the Flu at all until college, then I got it like 3–4 times, once a year in the first few months of the year… and shortly after starting to get physical with a new girl each time.