Americas Epidemics

I was wondering that when European came into contact with the Native Americans they spread many epidemic diseases among the native population because the native population had no resistance to the newly introduced diseases. So i was thinking that why wasn't the case that the Native Americans alos some epidemic diseases of their own for which they had the resistance for but the Europeans didn't so that those diseases quickly among the Europeans causing comparable havoc in their population in the same manner that their introduced diseases caused among the Native Americans. Is there any biological reason for why that wasn't so.

There was a lot of mortality between Europeans as well, that is well known. Between Africans mortality was even higher; theirs rate of survival in the New World was measured in months. The problem is that when a native died nobody replace them. When an European or African died there was a new ship on the way the replace the casualties. That's something to take into account.

Let's not forget that many native americans who died of "Disease" did so on forced marches.  If they were weakened to the point of succumbing to various diseases, it doesn't mean that they weren't still killed by whoever was marching them.

According to Jared Diamond (Guns, Germs, and Steel), people from the Old World, including europeans, asians, and africans did indeed have a stronger immunity system to diseases because of the following reasons:

Originally posted by calvo According to Jared Diamond (Guns, Germs, and Steel), people from the Old World, including europeans, asians, and africans did indeed have a stronger immunity system to diseases

This is only partially true. Eurasians and Africans would have immunity only to those diseases which did not mutate, as viruses and bacteria are prone to do frequently. If, for instance, you get your hands on an influenza vaccine that is from three or four years ago, it is unlikely to offer you any protection from the influenza virus you would encounter this year because the immune response and pathogen identification that it promotes won't apply to this year's strain.

This is due to antigenic drift. Antigens are the proteins present on the surface of a pathogen, and are used by the immune system in identifying and responding to the pathogen. When the RNA or DNA of a cell changes, the antigens change with it. Such mutations are much more common in viruses which consist of RNA because RNA, unlike DNA, has no error-checking mechanism and so transcription errors (and thus mutations) are far more frequent. What this all means, in practical terms, is that viral diseases often change so that no one, even in populations long exposed to that particular virus, has any immunity to it. Smallpox epidemics struck European populations with an average 60% contraction rate and of those a 20% mortality rate, according to Voltaire (which is comparable to natives), but unlike natives, Europeans had a method of primitive vaccination called inoculation by the 18th century; they rubbed pus or bodily fluids from an infected person into a cut, which reduced mortality by a factor of ten, to about 2%. Smallpox was an airborne disease and infection in the lungs was far more lethal and difficult for the body to defend against than infection from a surface cut, where it could resist the pathogen long enough to develop an antigen response.

Even though..... the percentage of Amerindians wiped out diseases was too high....., and the only likely explanation is that their immune system was more "naive" compared to Eurasians and Africans..., and that Eurasian diseases were much deadly.

Originally posted by calvo Even though..... the percentage of Amerindians wiped out diseases was too high....., and the only likely explanation is that their immune system was more "naive" compared to Eurasians and Africans...,

What does this mean? There is no difference between native and Eurasian/African immune systems. They both consist of antibodies and lymphocytes and inflammation response, and work identically.

It has been estimated that 95% of Amerindians were wiped out by diseases. If European colonists only had a "slight" advantage of immunology, they would have suffered a similar casualty rate: which would mean the "wipe-out" of literally ALL the colonists.

These numbers are surely too high. There are still millions of natives in south and central America. Some native groups in North America are larger in numbers than they were pre-contact (the Iroqouis are an example) while others have vanished entirely - typically those who did not have alliances with European powers and who lost their land. If natives were wiped out by disease, then it is strange that the disease should act in accord with colonial policies. Natives who interacted frequently with Europeans should have been harder hit than those who avoided them, but the reverse is true - native groups who sought to avoid contact altogether (such as the Beothuk or the Yana) were universally and utterly wiped out to a man, while those who dealt with Europeans (Sioux, Iroqouis, Cherokee but also Aztec and Inca) survived, in some cases in great numbers. The most intimate contact between Europeans and natives occurred in Mexico and Peru, where there are millions of natives today.

The natives would also have been introduced to these diseases centuries previous. Two groups of Eurasians had previously migrated to the Americas and settled in - the Vikings, in the east (although this contact was quite limited), and various arctic cultures in the west, who moved into the Americas from Siberia in repeated waves - at least two major waves (Dorset culture and Thule culture) of 2000 BC and 1000 AD, respectively, which spread from the Bering Strait clear to Greenland. In fact, since the emergence of Thule culture in the Bering Strait around 1000 AD, there was continuous traffic between Siberia and Alaska by the Yupik tribes, who today exist in both Siberia and Alaska and the islands of the Bering Strait. There was a continuum of Inuit cultures that extended directly to the frontiers of Amerind cultures, with direct contact (warring or trade) with such Amerind cultures as the Tlingit , Chippewa, Cree, and Montagnais Algonquians.

The spread of disease was always a two way street, but with the all other factors involved the natives were no match for the European aggression and desire for land. European colonies were wiped out on a regular basis but there was always more to take their place. The Eastern tribes of America began the famous "Ghost Dance" where they committed virtual suicide by running  into European settlements yelling at these "bringers of bad spirits"  to go away and never come back again. 

Originally posted by pinguin The main problem for Natives was not deseases, guns (they have them) or agression. The problem was they were OUTNUMBERED by the outsiders. That is recorded everywhere. Europeans just keep comming, while they could hardly stand the losses.

An associated problem with that is that many groups failed to act quickly and decisively to deny the enemy a base of operations and reinforcement. European states would never allow another power to enter into their territory and begin setting up towns and forts; they wouldn't even let armed men land on their shores or cross their borders whatsoever and would act immediately to repel any incursion.

Some native groups failed to do this. The Aztec are a famous example; Montezuma let the Spaniards land, let them roam for a while freely (gaining native allies along the way), and even invited them into his capitol. Had he immediately assembled his warriors and sent his army to ensure the Spaniards left Cempoala by sea or not at all, Cortes conquest would have been aborted. He had many further opportunities to get rid of Cortes; on the trip to the Valley of Mexico, he could have caught them in the mountain passes. At Tenochtitlan, he could have caught them on the southern causeway. Each time they would have been outnumbered and without benefit of thousands of native allies. It certainly wasn't impossible to drive Cortes off; the Mayans did it repeatedly and consistently, forcing the fleet to sail further and further along the coast until they arrived at Cempoala. Possibly Gonzalo Guerrerro was forewarning the Mayans though; his advice would have been respected since he had become a war chief in Chektumal. Montezuma, on the other hand, let superstition get the best of him and paid too much attention to his soothsayers and their omens, which rendered him indecisive.

Many other native groups allowed Europeans to enter their territory and occupy some part of it that they weren't using. In some cases, they managed to act rapidly but not decisively or consistently - an example is the Algonquian tribe near Jamestown, which alternated between attempting to repel the settlers and befriend them.

Well, Mapuches of Chile crashed Spaniards at first contact. They learned Spanish tactics and robb horses, and quite soon were fighting in an equal stand. They were never defeated.

Edited by pinguin - 21-Jul-2007 at 10:02