Why did Native Americans die from European diseases while Europeans didn't catch serious diseases from the New World?

Question

Why did Native Americans die of European diseases while Europeans didn't have serious diseases from the New World? I read that most Native American victims of colonization in the new world died of European diseases and not by battles. But why didn't European people catch some deadly disease from Native Americans? Was it because of better European immunity? Was it because Europe had better experience handling diseases? Or what factors played major roles in this historical exchange of bacterias and viruses?

Answer 1

One of the primary issues that affected the predominantly one-way direction of disease transmission between Europeans and native peoples was that European societies had grown dense. High population density can more readily lead to disease mutation and subsequent exposure, creating an evolving loop between the disease and antibodies. These evolving diseases can become quite effective at attacking immune systems. When introduced to native populations who had never encountered such a disease before, the disease found no antibodies to counteract its attack. Furthermore, the Europeans had a great deal of cultural contact and transmission through trade (additionally driven by early principles of an emerging paradigm called capitalism), which exposed large swathes of Europe to similar diseases -- consider the bubonic plague as the foremost example. The scale of contact between pre-colonization American civilizations was less than that of European civilizations, providing buffers between the major peoples (Mayan, Aztec, Incan). While these cultures had several large cities of note with high levels of sophistication and high population density, these cities were fewer in number and had less interaction between one another than European cities. Finally, the Europeans did suffer from several novel diseases, infections, etc in the Americas, but they weren't of the highly-communicable variety that so effectively ravaged the native peoples (think yellow fever, for instance, which is spread through mosquitoes).

Answer 2

Honestly those are good questions and I'm guessing that whatever antibodies the explorers had made them hardy enough to survive the change in geography as most of where they landed was in more tropical environments. However, I seem to remember some cases of syphilis and yellow fever but the EurAsians had developed genetic immunity and were able to overcome them quicker. Typically when a population has no introduction to a new strain of bacteria or virus then it eradicates the population as no one tends to survive to breed and pass on the mutation (how the person survived it is encoded in their genes). Of course we all know the stories of the Europeans practicing a sort of biological warfare by passing infected blankets to the Indians and some diseases are transmitted through physical (skin to skin) contact or are airborne (transmitted thru nose and mouth). Much of human civilization was transformed due to the lack of accurate scientific knowledge of disease that lasted well into the 20th century!!