I think 20-49

Any age group ... same with Hiv. You can pick it up as a baby or as an old person, It cannot be put down to an age group that is stupid. You catch it by blood contact with someone who is infected, whether it is from a blood transfusion, tattoo parlor, standing on a syringe or even sharing a toothbrush or razor with someone infected.

It's true you can get it at any age but some age groups are more likely to get it. Little children don't share syringes to shoot drugs and get tatoos, where older people have the same chance as the other groups to to encounter it as mentioned(toothbrush, transfusions etc) plus the risk from their behavior.