Globalization: Bigger is Better, Until Plagues Hit
A big societal factor that contributed to the appearance of plagues in history was the shift from a hunter and gatherer society to more of an agricultural society. Since hunters and gatherers were constantly on the move, they were never exposed to rotting meat and feces since they left that all behind as they moved. This would make sense why these people would not contract foodborne illnesses such as E.coli, Salmonella, and Staphylococcus aureus.
Another large societal factor that helped facilitate plagues was the introduction of an agricultural system. In addition to an agricultural culture, humans began domesticating animals for resources such as milk, meat, and work (plowing fields). When hunters and gatherers had previously been on the move, they drank and ate from many different areas, not one. However, once people became more sedentary and developed agricultural systems, diseases spread for numerous reasons. For one, domesticated animals and humans were sharing the same water supply so any diseases the livestock had, could be spread through the water system. Another reason for the spread of disease was now the fact that, unlike the hunters and gatherers, humans were stuck in one place with accumulating rotting food and animal feces. Lastly, when humans began to expand their society, they cleared forests in order to plant crops. By doing this, they took away the homes of many game animals. Now, mosquitos and flies that had previously fed on the blood of these animals, began to feed on the humans that occupied these areas. Some examples of the disease these vectors brought to humans were malaria and yellow fever from mosquitos.
As for humans now using the same source of water constantly, another problem arose: Typhoid. Typhoid is a disease that is spread by the oral-fecal route of either contaminated water or food. Basically humans, being permanently positioned in one place, used the same water to relieve their bowels and to drink.
Furthermore, being on the move meant hunters and gatherers were not moving in very large groups. Therefore, once people became more sedentary and populations grew, so did the ability for plagues to rapidly spread. These diseases that thrived in dense populations were known as “crowd diseases.” Some examples include smallpox, influenza, TB, malaria, plague, measles, and cholera. As we learned from the 1918 influenza pandemic, highly condense and populated areas of people only help to further spread contagious plagues. In this example, the influenza was hypothesized to have started at Ft. Riley, a packed army base. Since there were so many people all in one place, it was easy for this respiratory disease to spread quickly. Furthermore, from the film on the 1918 influenza, cities were highly condensed with people and there were often patriotic parades to support the Great War. These conditions with people packed like sardines in cities for events like this, also allowed for disease to rapidly spread.
In current times, there are numerous societal issues that negatively affect health and the spread of infectious disease. For example, climate change is a result of increasing levels of carbon dioxide and short-lived climate pollutants, a result of the machinery we use in our society. As a result of this, temperatures and sea levels rise, as well as extreme weather events. More so, this results in numerous exposure pathways for infectious diseases. Some examples include poor water quality leading to cholera spreading, poor food supply leading to salmonella food poisoning, and changes in vector distribution leading to the spread of malaria and Zika virus. In addition to climate change having a negative effect, the increase in density in cities and population in general is currently allowing diseases to spread. Just like the 1918 influenza pandemic and other “crowd diseases,” our current society allows for easy spread of diseases among large amounts of people.
References (Help Received)
Sherman, I.W. (2017). The Power of Plagues (2nded.). Washington, D.C.: ASM Press.
PowerPoint: The Price of Being Sedentary
In class handouts