Like most things in life (OK, like all things in life), the flu shot is not a silver bullet. Although the vaccine protects against the flu strains you’re most likely to get exposed to, it’s still possible to get sick—especially within the first two weeks after getting the shot. Your body needs time to build up the antibodies required to fight off infection, so the sooner you get the shot, the better. In the meantime, take care to avoid exposure to the flu as much as you can by steering clear of sick friends and washing your hands regularly.

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