Disease is a very interesting lens through which to study human behavior. There is nothing that will break down the man-nature divide that constantly informs human cultural relations with our environment better than infection of disease. It is impossible to ignore the effect anthropogenic pollution has on an environmental system during a cholera outbreak or even overlook the power of evolution during flu season. James Trostle says in his “Anthropological Contributions to the Study of Cholera” “an outbreak is an ideal moment for anthropologists and other social scientists to investigate disease: the insult is recent and noticeable, and people are still responding to it, revealing prejudices and assumptions about purity, pollution and social stratification (Trostle 97).”
As this quote indicates, there is an interesting dimension to disease that makes it more than just a bridge between man and nature. The most meaningful and harmful diseases, though adapted to human beings from nature, are transmitted to a person directly from another person. In no case has this agency of transmission proved more intriguing than in the transmission of disease from one civilization to another thanks to advances in the technologies of transportation. It is indicative of the technological state of our world now, however, that we no longer face quite the same immune system deficiencies between civilizations that were once the cause of great episodes of death, yet infectious disease is still a major cause of death in much of the world. What follows is a description of the history of the transmission of disease globally and a look into how global transportation technology is still the primary agent by which humans are threatened by infectious disease.
It is fitting that the switch from hunter-gatherer to farmer is what has led both to the development of most of the diseases that plague modern man and the development of the modern culture within which we experience the effects of these diseases. The increased contact with animals that came with their domestication exposed humans to many new diseases. Smallpox, for example, is closely related to cowpox and leprosy was transferred to us from water buffalo, influenza came from hogs and even the common cold originated in horses. The increased contact between humans that the agricultural lifestyle facilitated catalyzed adoption of these new diseases into the general human condition (Ponting 226).
Pollution similarly affected the new settled human. As Jared Diamond puts it in his Guns, Germs, and Steel: “If the rise of farming was thus a bonanza for our microbes, the rise of cities was a greater one, as still more densely packed human populations festered under even worse sanitation conditions. Not until the beginning of the 20th century did Europe’s urban populations finally become self-sustaining: before than constant immigration of healthy peasant from the countryside was necessary to make up for the constant deaths of city dwellers from crowd diseases (Diamond 205).” As Diamond points out, it took a little while for our forefathers to realize the connection between sanitation and cholera and dysentery. Just living together, however, was often enough. Studies have shown that many infections diseases are population dependant, for example measles will die out on islands that have less than 500,000 inhabitants and it is likely mumps and smallpox have a similar minimum host level (Ponting 226). As previously stated, however, the story of human transmission of disease really starts with advancements in travel.
In early modern human history there are many instances of transmission of disease from one civilization to another immediately after first contact. This is due to one civilization having developed some immunity to the disease by a lifetime of exposure and the other experiencing the great shock of not having that luxury. This was the case for smallpox in Rome starting in 165 AD and the bubonic plague that, between 1200 AD and 1350 AD, spread from Europe to China (Ponting 228).
The most jarring of all inter-civilization disease transport, however, occurred during the European conquest of the New World. Though exact numbers are not known, it is sufficient to say that between 1520, when smallpox first reached Mexico by way of an infected slave from Spanish Cuba, and 1618 Mexico’s population dropped from 20 million to about 1.6 million (Diamond 210). While many of these deaths can be attributed to the weapons of the conquering Spaniards, the diseases they brought caused the vast majority. In retrospect, it is quite tragic that this arbitrary environmental factor went entirely in the favor of the Europeans and no equivalent disease was transferred to them from the Native Americans.
It is in this last point where a very relevant connection can begin to be made between the relationship of technology and disease during the time of conquistadors and navigators and the relationship of technology and disease during modern times. Since long-range travel and transport began it can be said that the world has been shrinking. Contact between civilizations has been increasing markedly by the advent of transportation technology and for good reason; it is very profitable. Transportation technology continues to advance at a rapid pace and it has shrunk the world so much that we now have different buzzword for it: Globalization. In many ways yesterday’s galleons are today’s emails and cell phone calls. It is all part of increased global communication and trade.
So where does disease fit into this? Before answering that, lets take a step back and look at modern disease and medicine. Ponting points out that over the past two centuries people have been living longer lives and he attributes this to fewer of them dying of infections diseases. His explanation for this is not that what used to be common deadly diseases have become less virulent, though this has happened in some cases, and it is not because of modern medicine. He concludes “the major influences in reducing the impact of infectious diseases (have been) better diet and environmental improvements (Ponting 234).” Improved diet, especially, he points out has been instrumental in lowering child mortality rates. It follows from this logic that the modern civilizations that would be suffering the most from infectious diseases are those that still have dietary shortcomings and still suffer from poor environmental care. Indeed, this is the case.
Economically motivated developments in transport technology were the main agents of long-range spread of infectious diseases before the Industrial Revolution and they remain to be after, though in a slightly more indirect form. Returning to James Trostle’s cholera essay, his main conclusion is that poverty serves as a catalyst for cholera outbreaks in third world countries. It is alienation and a dearth of social welfare that serves to create this cholera state and it is the political and economic climate of the nation it is in that will ultimately help pull them out of it (Trostle). Now, just like it has been for centuries, it is the western technological advancements in transportation, driven by the economics of those nations, that are the agents for the states of poverty that are conducive to societal weakness to infectious disease. Morally there is little difference between infecting the Native Americans with disease for the sake of profit and allowing poor communities to succumb to diseases that would be eradicated with simply the improvement of living conditions.
The shrinking of the world by technological advancements in transportation and communication has created a very different but similar world as seen through the lens of disease. But it comes with it a lot of hope. Just as human contact is the agent for the spreading of disease, it can also be the agent for the eradication of disease. The amount of relief that can be given to the communities suffering from infectious disease is unprecedented thanks to advances in both medical and transportation technology. And just as the state of the global economy can be the cause of misery in some communities, it also holds the promise of bringing those states out of poverty quicker and more successfully than at any other time in human history. The story of human transport and disease is also the story of human progress and success in the face of disease. Thus, as is the case with all technology, the harm or help of transportation depends wholly on the motivations behind its use.
Diamond, Jared Guns, Germs, and Steel, "Ch. 11: Lethal gift of livestock," pp. 195-214. W.W. Norton & Co, 1997.
Ponting, Clive. "A Green History of the World," Ch. 11 pp. 224-239. St. Martins Press, NYC, 1991.
Trostle. James “Anthropological Contributions to the Study of Cholera.” Epidemiology and Culture.
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