I had the flu once, 25 years ago. I can't take Tylenol so it is hard to combat a 104 fever, which raged for days until and ice bath at the ER. It took me six months to get my strength back. I get the shot every year. Have not had the flu since. I am a fiend about hand washing. I know its not always effective against that year's strain, but it can lessen the severity if you get the flu. I don't see a downside for me.