system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 Why did contact with the Vikings not have the same effect on Native American population that contact with Europeans at a later date did?

After contact with Columbus and Europeans in the 14-1600's Native Americans lost massive amounts of people due to exposure to diseases they had no natural resistance to. Why wasn't there a similar effect when the European Vikings came to love settle in in North America. Wouldn't they have brought similar diseases with them? Wouldn't they have caused a similar effect?

EDIT. It seems like it comes to the point that Viking society wasn't dense enough to produce the plagues that the later settlers brought. I never would have thought about that. Thank you guys so much!!
gpt
That assumes they had any significant contact with a group that then had significant contact (before dying) with more natives. Knowing the vikings it's also possible they were terrifying enough that the natives stayed the hell away. Remember the Europeans also brought horses, lots of people, and they intended to bring people and gold home. The Vikings were not thinking on that scale, but on a much more personal kind of scale. 

Plus, the vikings could have met some brutally stiff resistance, while the Europeans had firearms plate armor, and horses.