Still looking for a fever

Many people have recently shared The Worst Animal in the World, the story of how we unwittingly domesticated Aedes aegypti mosquitoes and helped them to take over the world. I enjoyed reading it and learned a lot but alas, not about the question that is currently bothering me.

[T]he parasite that causes malaria was not originally present in the New World; notwithstanding the fact that [quinine] appears to target Plasmodium’s metabolism, what is it doing in the tree, and what indigenous fevers did it cure, and how?

Different mosquito, different disease, so of course I can’t fault the Atlantic article.

In looking around for answers, I’ve learned a little bit about how the malaria parasites might have moved from gorilla to human and then, as a result of the slave trade, how they adapted to more than 70 different anopheline mosquito species around the world. Also, Plasmodium species infect birds, mammals and reptiles in South America. But my questions remain?

Were there forms of human malaria in South America before the slave trade?

What fevers did local people use cinchona bark to cure?

I’m sure there is an answer. I just have not been able to find it. Someone — anyone — please help.