Small pox, hepatitis, and and typhus all did massive damage to native american populations just before the major European conquests of the 1500s, because of the natives' lack of prior exposure to the diseases. Did the Europeans encounter any diseases that were similarly devastating to colonists?

by x3nodox

If not, why were the diseases of Eurasian and African origin so much more deadly? If so, what were the impacts? Did they travel back to Europe with returning conquistadors/others?

Mictlantecuhtli

There is always more room for discussion, but perhaps the section titled Native Americans and (European) Diseases in our FAQ as well as this /r/badhistory post on the Myths of Conquest will answer your question.