Every year around this time, you see reminders to get your flu vaccine, and every year, a bunch of people don't do it, for one reason or another. "I never get the flu anyway." "The flu shot makes me sick, so why bother?" "It doesn't even work, so what's the point?"
The point is that in addition to protecting you against the most common strains of the flu each year, we need a critical mass of people to get vaccinated to prevent the flu from spreading at all, so people that can't get the vaccine - the very young, elderly, or immunocompromised - are protected, too. This is super important, since this is the group most likely to suffer serious complications if they get the flu, including death.
This is called "herd immunity," or "community immunity." The point is that if a high enough percentage of people are immune, there are too few susceptible people for the vaccine to spread. We've successfully done this with diseases like measles and mumps (except where anti-vaccers have caused outbreaks).
So YSK, get a flu shot, because it'll probably keep you from getting the flu, and grandma needs you to get the flu shot so she doesn't get the flu when you sneeze in the supermarket. Grandmas and newborns everywhere thank you.
