system
Given the following post, respond as if you're commenting on Reddit:
human
[War of the Worlds] Would Martians win if they attacked Pre-Colombian America instead?

As y'all know, until the 1500's, the world was divided in two kinds of human beings: the relatively parasite-free peoples of the Americas and the Pacific and the germ-ridden, animal husbandry-ers, Black Plague survivors of the Old World (Africa, Europe and Asia). Just by making contact with the people from the Americas, Old Worlders caused lethal pandemics that possibly were what caused most of the death toll in the first decades after first contact. It was specially ugly to Amerindians who lived in cities, like Mesoamericans.

So, I would think Martians attacking even medieval China or Europe would end up dying, infected by viruses and other germs. Would they stand a better chance by attacking medieval Mesoamerica, which human population was much less a carrier of germs?
gpt
It's a common misconception that the Martians were defeated by disease. That's really a simplification.

Martians eradicated all microbial life from their planet generations ago. They had no defense against them.

Catching a cough from a human was the least of their worries. Most diseases are specific to a few species anyway. No, what killed them first were putrefying bacteria and fungi, which probably infected them as soon as they landed and breathed our air. 

Animals on Earth have a natural resistance to these organisms while alive, but the Martians didn't. The whole time they were on Earth, they were rotting from the inside. 

It didn't matter where on Earth they landed. If it was a place where dead things rot, then it would have killed them just as quickly.