I used to get it every year when I lived with my grandparents. I then proceeded to get it for my kids every year. One year I got lazy and just didn't do it. I didn't notice any difference. We are not a family that seems to get too sick. I get the odd stuffy nose and head cold, but it lasts only days for the most part and nothing that kicks me on my butt. If I have a stomach flu go through the house, I get that every time! But we rarely have problems with that, and in reality, they only last 24 hours for the most part. My kids rarely take days off school for sickness. So, I just don't bother anymore.