Heads up, Creators: On Dec 13-14 you may see a noticeable decrease in your sub count as we remove spam subscriptions. If spam is removed, you'll see a YouTube Studio alert: https://goo.gl/qGDBvX This should help give you confidence that the subs you do have are real fans!
How about you just remove accounts that claim a person is over 120 years old instead? (I say 120 because I don't know if anybody has reached that and the Bible says something about it.)