I know that diseases such as small pox brought over from Europe by explorers caused an epidemic which killed many native people. I'm wondering if there were any diseases which the natives passed on to the Europeans in a similar manner.
hi! this is one of the most popular questions in this sub! there's always room for more info (e.g. regarding the initial Spanish explorers specifically), but you can get started in the FAQ*. Despite the section title, there are several posts asking about Europeans picking up diseases from the Americas.
Native Americans and (European) Diseases
*see the link on the sidebar