Hello everyone.
I have begun consideration of timelines that will cause an alternative discovery of America, and thus have to consider one of the most devastating consequences of that discovery. Smallpox devastated native american populations in our history, and thus one has to weigh the strong possibility of alternate contact doing much the same. So let's put our heads together and consider a few details.
1. As I understand it, Europe at the end of the 15th century was practically wallowing in disease due to our domestication of animals for food and labor. It is my understanding that even if smallpox had not been a thing in the new world that it was only a matter of time that some disease that Europe would have considered serious would have proven utterly lethal in America. Does this apply to most other parts of the world, or is Europe especially toxic when it comes to disease? For example, if China had made contact in roughly the same period (the treasures ships of the Ming are a favorite example with alternate historians) any less dangerous than America?
2. Assuming an early enough POD to make the other factors feasible, would a native American civilization have any better luck with illness if THEY made contact elsewhere? Let's not just factor in Europe here- what are their odds of survival in Asia, Africa, Oceania, etc. If disease is still too deadly to survive, what are the chances it gets back to the mainline versus remains devastating to a local trade site or colony?
3. Let's consider technology, custom, and farming as well. As said above, one supposed factor in how dangerous Europe was to the new world revolved around their domestication of livestock. Is there a time in history in which such domestication was absent? Could an earlier contact avoid the pandemic (would the native americans have better luck dealing with Carthage than Spain)? Are there any examples of civilizations in conventional history advanced enough to make potential contact on a meaningful scale without running the risk of continent wide death?
4. On the flip side, are there any examples you can imagine in which a pandemic would have been WORSE (with a larger or even total death toll)?