system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why were the European Colonists not ravaged by American disease unlike the Native Americans who were ravaged by European/African disease?
gpt
There's a great CGPGrey video on this on YouTube. Its called Americapox or something.

I think it largely states that it was due to the americas not having domesticated animals which humans stay in prolonged contact with (in densely populated areas like cities), and that most dangerous diseases spread from animals to humans.