I disagree that not understanding the concept of Original Sin exempts a person from the Curse...for all have sinned and fall short of the glory of God (Rom 3:23).
Also, Original Sin is not simply the knowledge of Good and Evil, for God Himself had that knowledge long before the first Sin was ever committed, and He is not under the curse, but is indeed pure and holy, even as he knows the depths of evil. Thus simple knowledge of good and evil is not the Original Sin, but disobedience to God is the Original Sin. God said, "Don't eat the fruit." The devil said, "Do it!" Man and woman obeyed their desire and disobeyed God.
Disobedience is the First Sin. The concept of Original Sin is not just that the First Sin was committed, but that it allowed for general sin to enter into daily life as a constant factor, even to the point where it was passed on at the genetic level. Things did not break, feelings were not hurt, abuses were not committed, injuries were not inflicted until the act of disobedience was committed. Now, this act was attractive to Adam and Eve. They wanted knowledge...it seemed like a good thing, and even had some edifying results. They knew that God had the knowledge of good and evil, and He was Good, so why wouldn't the knowledge of good and evil be good for them, regardless of what God was trying to shield them from?
Perhaps God was even saving the fruit of the Tree of Knowledge for Adam and Eve to eat from later, as they matured in Eden. But they weren't ready, and God knew this, and he commanded them not to eat, but instead to partake of any other fruit in the Garden.
Thus, Original Sin not only includes the act of disobedience, but the resulting infestation of sin throughout people in history. You and I were born to sin. There is no one who has ever been free from sin. It isn't Adam and Eve's "fault" that we all struggle with sin, because the fact of it is we are responsible for our thoughts, deeds, and words. So, even though the opportunity to sin didn't appear until Eve seduced and Adam acted, even though sin has multiplied its damage exponentially down through history, and even though we are all born into sinful environments over which we have no control (everything from abusive homes to arrogant parents to self-destructive communities, etc.), we are fully responsible for the sins we choose to commit, which are legion.
So, even if you are born in a vegatative state, unable to conceptualize even basic tangibles like food or touch, you are a sinner, living under the curse of Original Sin contributing your own sins to the planetary sin-debt to God and fellow man.