Just as the title asks: when colonizers came over to America, were they also affected by diseases that the Indigenous people had? Like, from what I was told, the reason why illnesses like smallpox greatly affected Native peoples was because they had never encountered it before so they had no immunity to it, so the opposite logically has to be true for illnesses the colonizers didn't have immunity for, right?
I commend to your attention the appropriate section of the FAQ, which addresses both notions of European invaders versus American diseases and Native Americans versus European diseases.