Well, it would make sense that the Native Americans living in your expanding colonial territories would still suffer the effects of disease.Be me.
Create the custom Kingdom of the Canaries, based off of the historical Norman adventure state that existed there in the early 15th century
Colonize Brazil right off.
Move my capital to Bahía.
Think I'm a smart boy for basing my nation in the New World and getting a thirty year head start on colonization while still being Western.
Now it's the 1590s, and my country has just started to get the standard "Native Americans fall apart due to disease" events, despite that I'm originally European, and that I've been in contact with and bordering other european powers for decades now.
Is this a bug, or a brilliant event chain?