Only Get The Flu Once A Season
Many people assume that if they’ve had the flu recently, they can’t get it again -- and thus don’t need to get the vaccine. That’s not the case because flu infection can happen from more than one strain of virus.
In any flu season, there’s usually both Type A and Type B influenza in circulation. Both can cause the flu. It’s quite possible that you could get infected with one type and then the other.