The Origins and Effects of Disease During the
European Conquest of the New Worldby
David KrzywanskiThe European conquest of the new world was most commonly attributed to the superiority of the Europeans in all the facets of their confrontation. They had the superior weaponry, and were thought to have a superior intellect. After all, they were just bringing "civilization" to the new world, right? It sounds nice when you are learning about Columbus in grade school, but the traditional story is pretty far from the truth. The truth is that the Europeans, when they discovered this was a brand new world and not the spice islands, sought to rape the land for its gold and natural resources and enslave the Amerindians (native Americans), who were regarded to be less than human. One has to wonder why it was so easy for the Europeans to impose their will on the Amerindians. Was it solely because the Europeans were superior technologically and intellectually? Unfortunately the answer is not that simple. The Europeans were superior in those areas, but the bulk of the disaster they imposed was not what they knew, but what they brought with them, disease. Disease, on the epidemic level, is thought to be the major factor in the decline of the Amerindians during the age of discovery. Before I go any further, I feel that I should clarify the difference between the terms epidemic and endemic disease. An epidemic disease is a disease that enters into a population and completely ravages it. Epidemics are particularly destructive because they are usually diseases that have never been introduced into that specific population. A good example of an epidemic is the bubonic plague, or smallpox. Smallpox uncontrollably ravaged Europe for more than two hundred years. The disease was very deadly and had never been seen before in Europe. As a result millions died. The endemic disease is quite different. It is the type of disease you contract as a child, fight off, and develop an immunity for in adulthood. An example of this is chicken pox. Most Americans have suffered, or will suffer, from chicken pox as a child. One becomes sick for a little while, recovers, and never suffers from the disease again. Now with the differences between epidemic and endemic clarified, I will move on to the origins of disease. The origin of disease is a relatively easy idea to understand. Human beings on the planet went through a transition from nomadic, hunter-gatherers to the sedentary lifestyle by utilizing agriculture. This brought relatively small bands of people together into villages, which eventually became towns and cities. In Europe, the people not only used agriculture to feed their growing population, they also domesticated animals for a food source. As the population grew, the size of the herds of animals needed to feed the people grew as well. All animals carry disease and parasites, both in the wild and when they are domesticated. However, domesticated animals proved to be a breeding ground for disease. These domesticated animals were in close contact with the growing population of Europeans and it was not long before the disease was transferred to humans. The microbe, virus, or parasite only had to adapt to living in a human host. The process was relatively quick, and thus the epidemic disease was born in Europe. This was not true for the Amerindians in the new world. Though they had made the step from the nomadic life to the sedentary life, they did not domesticate animals. They based their nutrition on cultivated crops such as potatoes and corn. When they did eat meat it was hunted. A lifestyle like this avoided the transference of disease from the domesticated animal to the human. One can now see the differences between the continents with respect to the spread disease. One should not underestimate the evolutionary intelligence or the power of these diseases. However, one has to remember that in order for these diseases to be effective the conditions must be correct. Microbes that cause epidemics often need a pool of several million people in order to sustain itself (Cowley, 1991). The diseases can not cause an epidemic in a town or village of one thousand people. The people of the village would either die off, and with them the disease, or they would get sick and eventually become immune to the infection. But, one thing must be made clear; it is not in the interest of the bug to kill the animal or human it invades. The idea is to keep the host alive so that the bug has a source of food. If the host dies so does the bug. If the host dies, it is often just an unintended by-product of the bug's attempt to spread their offspring, as will be demonstrated in the next paragraph. These are very clever organisms. They find a way to survive and reproduce. Many have heard the saying, "you can stay alive by living in your children," well this is also what pathogens do. What one sees as symptoms are really just the bug manipulating one's body to spread the new bugs they have produced. Sores and skin lesions are one way of spreading disease through direct or indirect contact. They also can make the host cough or sneeze, thereby broadcasting the bugs to prospective hosts (Diamond 1992). These are just a few ways in which diseases are spread, but one can still see why it is necessary for there to be a large population in relatively close proximity in order for the disease to sustain itself. One can now understand how a bug can move within a population, but how do they move from population to population? One way disease can move from population to population is through those who are trying to flee the illness. Another clever device the bugs have developed is what is called an incubation period. The incubation period is the time frame where an infected individual shows no symptoms of the disease, but is a carrier and can infect others. There are several reasons why the infection is not showing any symptoms. One is that it is lying dormant in the host. The bug has entered the host's system, but has not begun to reproduce or effect any of the body systems. A second possible explanation is that the host's natural immune system is doing a good job of fighting off the illness for a while, but it is soon overtaken. The result is the appearance of symptoms. This is just how disease migrated from the old world to the new world. For example, a sailor or slave who seemed uninfected gets on the ship for the journey. Usually the infected man would die during the journey, but if his clothes made it to the new world, the disease could be transmitted. Transoceanic spreading was probably done in this way. Smallpox in a human has life for about one month, but if its wrapped in cotton it can live for up to seventeen months (Snow, 1988). This method did occur, but was not the primary mechanism for the spread of infectious disease in the Americas. Let's assume that a disease had an incubation period of ten to fourteen days. This is sufficient time for a person to walk to a neighboring village and spread the infection. The problem was compounded further when people began to ride on horseback. This illustration demonstrates how simple the process of transmission really was. If disease could be spread so easily how did anyone survive? The answer lies in genetics. Through the process of natural selection the "weak", so to speak, are weeded out. Natural selection is a process of nature where those who have a competitive advantage to survive in a particular environment survive and reproduce. Thus, passing on crucial genes to their offspring. If a disease comes to a population and devastates ninety five percent of the people, the five percent who did survive may have genetic resistance to the disease. Survivors whom are not genetically resistant can contract a weakened form of the disease. If they beat the disease, they are said to have exposure resistance. These survivors could then pass their genes to offspring, creating a new generation of immune individuals. It is important to remember that usually genetic resistance is used to describe an individual, whereas exposure resistance applies to a population. When a population is devastated and then slowly grows back to larger levels, it is through the process of natural selection I discussed above. That population that does not get the disease any longer is said to have exposure resistance. The phenomenon I have just described is how a population, in the long run, beats an epidemic. The worst part about disease is the devastating effect that it can have on a civilization. Its most disastrous effects are on those peoples who have lived in isolation for long periods of time, and then are visited by outside people either in the form of invasion or for commerce. People who live in isolation in a particular habitat develop immunity to the infections of their environment and live healthy lives. The problem begins when outside people bring foreign pathogens (disease) into the community. The isolated people have no immunity what so ever to these new pathogens. They wreak havoc on the population, reducing their numbers severely, if not killing them all. Had these people ever seen these diseases before, and dealt with them, their death rate would not have been so severe. The moral of the story is that outside disease brought into an isolated place can decimate the population of a civilization and pushing them to extinction. The European conquest of the new world cannot be completely understood just by understanding the nature of disease. It is also necessary to understand how native and introduced diseases affected the populations of the Europeans and the Amerindians. The truth of the matter is that the Europeans and the Amerindians did not respond to the same infectious disease in the same way. Some diseases were more devastating for the Amerindians, and some were more devastating to the Europeans. The critical factor in the disease exchange between the two cultures was timing. One knows the major killer of the Amerindians in the New World during the sixteenth century was smallpox, a disease that Europe encountered many years before. For a long period of time smallpox ran rampant through Europe killing upwards of seventy five percent of the population. The disease did not strike only once. It would strike, kill of large amounts of the population, and when the population could no longer sustain the disease, it would die out. Then, the population would slowly grow back until it reached a size that could sustain the disease, and it would strike again. This pattern would continue until the disease developed from an epidemic disease to a endemic disease. At this juncture, the children of the population would get it, fight it off, and in the process become immune to it for the rest of their lives. Most Europeans who reached adulthood were immune because of this. When smallpox is contracted during childhood one either fights it off or dies. Statistics show eighty percent of smallpox victims were under ten years of age, and seventy percent were under two years of age (Crosby, 1986). Smallpox was truly a childhood disease. Small pox was not the only infectious disease to invade Europe. Measles, diphtheria, wooping cough, chicken pox, malaria, typhoid fever, yellow fever, scarlet fever, and influenza also struck Europe. However, none of these diseases were quite as severe as smallpox. It seems that Europe not only saw the most serious of diseases but it also saw a great variety of disease. This set the stage for a Europe that was well equipped to fight against infectious pathogens. The Amerindians, though, lived in a very different place. America probably had its share of infectious disease, but certainly not to the same degree the Europeans did. Known diseases indigenous to the new world were: venereal syphilis, hepatitis, encephalitis, polio, and some varieties of tuberculosis. As one can see, the Amerindians did not see nearly as many diseases, nor did they see the same variety of disease. These pathogens probably took their toll on the Amerindians, but we really can not be sure since the Amerindians never really recorded size of populations in written form. Amerindian populations were also scattered over a very large distance, and individually tended to be too small to sustain a major epidemic. These factors lead one to the conclusion that the Amerindians did not build up a great immune defense system like the Europeans. This made them very susceptible to the diseases eventually brought over by the Europeans. Introduced disease did not have a profound on the Europeans. There is only one disease, syphilis, even being considered as a disease brought back from the new world. If syphilis did come back form the new world, it did not come back in any large quantity. The only way it could have gotten back to Europe was when Columbus brought back a few slaves with him on his first return voyage. It is also believed, in some circles, that the Europeans had seen a form of syphilis before, and this could explain why it did not have any great effect on the population. I tend to agree with the theory that syphilis was an introduced pathogen and its lack of potency was due to the already built up immune systems of the Europeans, and the small number of people who could have transmitted the disease. The introduction of smallpox into the Americas had a very different effect, although it was not immediate. Smallpox first appeared in Espanola in 1518-1519. The disease was not transferred by Columbus and the voyages of discovery. Major invasion of infectious disease did not occur until settlers came with African slaves came to the new world. The disease could be carried on the clothes of slaves ( increasing incubation period, so disease could make the voyage across the Atlantic), or with the sick children of the settlers. Smallpox had finally arrived, and in most of the Amerindian populations it encountered it killed off roughly one third to one half of the population. A specific example of this devastation was Cortes' invasion of Mexico. Before his arrival, the Mexican population was estimated to have been around 25-30 million. Fifty years after his arrival, the Mexican population was cut down to 3 million, attributable mainly to infectious disease. Here we see the real effect of the invasion of the Europeans in the new world. With no natural immunity to help them in their fight against these pathogens, the Amerindians were massacred. The effects that pathogens had in each of these cultures can now be seen. The Europeans came out relatively unharmed, whereas the Amerindians were devastated. These results have direct correlation with the amount and variety of disease seen by each culture. Why did Europe see so many diseases? The answer lies in commerce. Europe in the sixteenth century was heavily into trading with foreign lands. This was their primary reason for finding the new world: they were looking for a direct route to the spice islands over water. These types of voyages to Africa, all over the Mediterranean sea, and even by land to Asia exposed them to a great number of cultures in a great number of different environments. As a result, Europe turned into a giant disease pool. When they finally got over all of these diseases, they developed complex immune defenses. Conversely, the Amerindians were relatively untraveled and saw only a small number of diseases, located around only a few tribes, and lived in a similar environment. Europe's imperial hunger before, and through, the age of discovery ultimately saved them with respect to the great disease exchange that occurred with their contact of the Americas. Only one major question remains to be answered. I have explained how disease works, why it worked the way it did, and now I will answer the question of what impact did this have on the actual conquest of the new world by the Europeans? The answer is not surprising. Disease had a great positive effect for the Europeans and a dramatic negative effect for the Amerindians, the impact was even greater than that of the invention of gunpowder. This is true because gunpowder and muskets were eventually turned against the Europeans but disease only killed Amerindians. Europeans who were entering the new world for settlement, or to loot the cities for their gold and silver, often were met with some less than effective native military resistance. Why was this? Were the Europeans so advanced that they were just overwhelmed by them? Not hardly. In most cases European disease seemed to find its way into the Amerindian settlements long before the actual Europeans did. As a result, when the conquistadors got there all the natives were sick and dying, or already dead and gave little military resistance. This proves to be the major reason that the Europeans came in and made their way through the Americas with great ease. For example, in 1519 when Cortes landed in Mexico and was preparing to invade Tenochtitlan, (capitol of the militaristic Aztec empire), with only 600 men, and after battle escaped with only one third of his men. In 1520 smallpox reached Mexico. The epidemic proceeded to kill nearly half of the Aztecs, making them relatively easy to conquer when Cortes reentered Mexico, further adding to the myth of Europe's invincibility. This scenario reoccurs throughout the age of discovery, and adds to the idea that it was not Europe's technological superiority, but the superiority of their disease that is most responsible for their conquest. Disease also worked for the Europeans psychologically. The ease of their movement through the Americas further supported the idea that God wanted Europe to expand and eventually control the new world. John Winthrop, in 1634, said, " For the natives are all near death from smallpox so as the lord hathe cleared our title to what we posses." A Frenchman wrote, " Touching these savages, there is a thing that I cannot omit to remark to you, it is that it appears God wishes that they yield their place to new peoples." Nothing could have been better for the European psyche. Not only were they taking what they wanted from the new world without regard for the Amerindians, but they also felt that this was god's will. In my view this probably fueled the European fire for conquest and expansion more than any other factor. It also restored the faith in the church that was lost during the middle ages, making conquest in the name of Christianity their excuse for an injustice that was certainly fueled more by commercialism. There was only one real problem from the European's point of view. The populations were being almost completely eradicated and this is not what the Europeans had in mind. They wanted the Amerindians for slave labor, translators, and guides. This posed a problem so the Europeans kept bringing in more African slaves to compensate, and unknowingly undermined everything they were trying to do. More African slaves brought over more African disease and in turn more Amerindians died. Well, the Europeans did not let this stop them. The loss of Amerindian labor just meant more African labor was needed to build their cities. Europe really paid no attention to Amerindian die off, and kept moving on. The Amerindians really were in a no win situation. At least from their perspective. They were totally surrounded by death, either from disease or war. Through this whole conflict the Europeans and the Amerindians could only agree on two things: 1) disease was a dreadful and divine punishment, and 2) whites were immune to the disease that ravaged the Indians. Just these two facts were enough to beat the Amerindians mentally. The natives began to lose faith in their gods, and even began to believe that their gods were on the European side. This led the Amerindians to commit suicide, or surrender to the Europeans because they felt resistance was futile. The mental state of the Amerindians at the time also can help explain the ease of European movement in the new world. Their loss of faith in their religion made them easy converts to Christianity. Disease seems to have undermined the Amerindians ability to resist the European imperialism both physically and mentally, making them easy targets for conquest. As Europeans entered into the new world they met very little resistance. In grade school one learned that this was because the European civilization was much more advanced, and that Europe did the Amerindians a favor when they came and conquered them and tried to make them part of a European colony. In reality, the Europeans were doing them an injustice, not a favor. Their efforts completely destroyed a way of life, and almost caused the extinction of a race of people. Why was this so easy for Europe? It was that invisible weapon they unknowingly carried with them all the way from Europe. Disease. Several pathogens, primarily smallpox, physically and mentally beat the Amerindians, most of the time before conquistadors even got there. Superior weapons and technology helped, but it was disease that caused the ultimate demise of America's great pre-Columbian civilizations. The truth should be known that it was not a greater race of people that took the Americas from the natives, it was the disease that accompanied an average race of people that made the difference in the conquest of the Americas Bibliography
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