Bubonic Plague
The bubonic plague is one version of a fatal flea-borne illness plague, which is caused by the bacteria called Yersinia pestis that ravaged the human populations in the fourteenth century. The bubonic plague is mainly transferred through fleas that originated from dark rats from the Southeast of Asia and that migrated to Europe by the sixth century. It was well known within the city walls and villages since they were travelled by ships with explorers.
Since the beginning of the 1300s, Europe had multiple wave attacks of the bubonic plague epidemics that were endured until the late 1700s. Since the plague originated from Asia and travelled along business routes into the dark ocean and the Mediterranean ocean, it rampages Italy and most other parts of the country such as France and the north European countries.
Colony of the infected rats were instituted in North India but some of these rodents infected traders along the routes and have been travelling throughout the middle east alongside Taiwan. After the 1300s, dealers who travelled west north to avoid such high death rates without realizing they have travelled into Russia, which constituted a large infected rodent population at that time. Even though the plague has been spreading around the Asian countries, most of the damage has been dealt within the walls of England.
The Englanders were oblivious of the causes of the plague but by the time they had figured it out, they were already too late to save almost more than half of the population. The bubonic plague is mainly spread by infected fleas from small animals. It may also result from exposure to the body fluids from a dead plague-infected animal. Since the plague is caused by Pestis, the Pestis enters in this sting and flows through the lymphatic structure to the nearest lymph nose where it duplicates itself.
The lymph nose then grows inflamed, nervous and uncomfortable, and is called the “Bubo”. Once this process continues to grow, the infection that inflamed the lymph nodes will turn into open sores filled with pus. Compared to rodents, this infection on humans are more severe and will further spread into the lungs, which leads to a serious form of pestilence called pneumonic infestation.
The bubonic plague had major affects on the human population. The bubonic plague had major impacts on the social, economic, and environmental aspects of Europe. The social and environmental impacts on Europe was that the villagers were not able to produce enough crops due to the declined population and due to the lack of natural essence and nutrients needed to harvest the crops, thus, farm expansion had come to an end by the 1300s.
Slightly productive lands such as the grasslands and meadows had been abandoned. The Grasslands, heaths and meadows had been transformed to farming, reducing the amount of protein in diets and reducing nutrients for the production of fertilizer, which subsidized to a decline in crop yields.
Furthermore, the social interventions were to rebuild the society after its plague-based breakdown. Europe was enduring its longest economic depression. Since the production of linen and cotton became very costly and time consuming, the production of wool was increased so that the people were able to get them for a low price while trying to survive the hardship. However, metal and glass industries were growing and they were being used to rebuild the nation back into its full potential. The opportunities of the plague left successful towns into ghost towns where resources and necessities were available for a start-up.
This start-up revolutionized a new colony. For example, the use of free labor in the 1300s contribute to inventions such as gears and suction pumps for mining purposes. Europe was benefiting from geographical advantages because they had a variety of very slow-paced rivers where supplies and goods could be transferred. This made the process easier and cheaper rather than transporting goods across land by animals since breeding animals were more complicated. Europe had just enough mountains for the slow-moving rivers useful in transforming water movement into mechanical power.
The shortage of labor increased the demand for slaves, cutting into the demand for free labor. Wealthy merchants competed for servants to staff their households while craftsmen and shopkeepers felt that they had to keep slaves to manage. Cobblers, carpenters, weavers and woolworkers bought men and women from the slave dealers to help in their industries meanwhile more slaves were put on the market as hungry parents sold their children, preferring their children’s enslavement to watching them starve to death. Now that villages are keeping the contamination of the plague out of their walls, they took means to contain the plague.
Medical interventions were taken place by trying to figure out the origin and cause but because of the time and period, it was very complicated to proceed with treatments since there were no knowledge of the topic. This led to other beliefs and measurements for the people. The cause that the people believed in was that they had a mindset of spirituality rather than believing there were anything physical. The belief in witchcraft was strengthened since there was panic.
The people believed that the end of the world was at hand, some groups engaged in orgies. People called the “Flagellants believed with others that the plague was the judgment of God on sinful mankind.” (The Black Death and early public health measures) This impact was more psychological rather having scientific reason for the cause of the plague. Other than religious beliefs, there were the numerous plague “cures”.
What was done was that the people would strap live chickens around plague buboes or drinking potions laced with mercury or arsenic. This treatment did not help nor did carrying sweet-smelling flowers and herbs or ornate pomanders to purify the air. When the Black Death spread through Italy in the mid-1300s, major harbors began turning away ships that were suspected of coming from infected areas. For example, leaders in Italy was the first to validate a very sophisticated protective procedures against the black plague, which was to close the city’s water to major body of water vessels, and quarantining travelers and legitimate ships to days of isolation. Other Italian cities tried similar measures.
The northern city of Pistoia introduced restrictions on imports and exports, travel, and market trading were all taken care of. But at least more than half of the population died because those restrictions had no effect. But Milan avoided a major outbreak and this was due to the control measures taken by city authorities, including sealing up houses after the plague was discovered there. These preventions took place to contain the spread of the plague but more or less, there were none to minimal effect.
The bubonic Plague fits perfectly into the ecological/evolutionary model since only a few genetic changes, representing both gene gain by lateral transfer and gene loss by loss-of-function mutation (pseudogenization), were fundamental to this process. The emergence of Y. pestis fits evolutionary theories that emphasize ecological opportunity in adaptive diversification and rapid emergence of new species.
In today’s society, many ongoing infectious diseases have arisen throughout time and continues to make threats to the people’s health. In some cases, brand new diseases have produced societal catastrophes with extravagant effects on the people. The bubonic plague, which rose from the Western civilization, is a subject with as much fascination for social scientists as for most scientists, especially anthropologists. The genetic markings lead to radical changes that may be relatively fresh and discrete and are new bacterial pathogens.
Microbiology was the least evolution focused on of the biological science but with the use of today’s technology, brand new developed experimental approaches have completely changed its ways. These tools are being applied for several levels and in several different model systems. Bacterial experiments in which controlled variations are recorded during a long time of an original clone are now providing experimental tests of evolutionary and genome adaptation.
For example, in the show called “Grey’s Anatomy”, one of the characters successfully rewired a gene from a harmless, benign tumor to make it work with a patient’s unhealthy gene to find a way to cure the uncurable patient. With the use of genome mapping, they were able to reengineer the bacteria to make it healthy enough to inject into the patient. As anthropology goes, the main purpose is to figure those specific genetic changes that are responsible for the change in the immunity of the bacterial genes and to control the behaviors by which they led to increased fitness.
The experiments of these evolutionary history have been distinguished between the two genetic variation and phenotype. Data and statistical programs can look for mutations of the different type of genes that can suggest how mutations in them were wired. However, with these statistics, the conclusion remains uncertain until the mutations are correctly categorized into how they became about.
The same molecular biology tools developed for bacterial pathogenesis studies provide the experimental means to test adaptive evolution hypotheses directly. Directed mutagenesis to eliminate gene function followed by virulence tests of the isogenic parent and mutant strains is fundamental to pathogenesis research. In like manner, allelic-exchange or site-specific mutagenesis can be used to compare ancestral, intermediate, and evolved alleles to test hypotheses about the evolution of virulence.
Allele-specific effects on function (e.g., catalytic activity or binding affinity) can also be evaluated by biochemical and structural biology assays and related to in vivo fitness. Thus, sophisticated genomic analyses to identify candidate adaptive genetic changes and molecular pathogenesis methods to evaluate the functional significance of these changes and their effect on in vivo fitness can be used to deduce the genetic and molecular basis of adaptive evolution. While this can still be a tall order, the molecular biology tools and model systems are available for many bacteria.
Gene Gain and Gene Loss are Both Major Drivers of Bacterial Evolution
Evolution can result from the gradual accumulation of many genetic changes of small effect or by a few key genetic changes of large effect. Bacterial evolution is frequently characterized by the latter, often due to the very high rate of lateral gene transfer among prokaryotes. Mobile genetic elements, including plasmids, bacteriophage, and genomic islands, are constantly being exchanged among bacteria throughout the environment, in what Joshua Lederberg once referred to as the original world wide web.
The impact of lateral gene transfer on bacterial evolution is exemplified by the emergence of “superbugs” that have acquired antibiotic resistance and toxin genes on plasmids or phage-related chromosomal islands. The pathogenicity of Salmonella enterica is a consequence of many virulence genes that were introduced by lateral transfer and incorporated into chromosomal pathogenicity islands.
The evolutionary significance of gene gain by lateral transfer has long been recognized. In contrast, the contribution of loss-of-function mutation (pseudogenization) to adaptation has only recently been appreciated. It was initially assumed that pseudogenes would be relatively rare in bacteria because their genomes are small and gene dense. However, the recent ability to compare the sequences of orthologous genes within a clade has revealed that pseudogenes are a common feature of bacterial genome.
Most are due to nonsense point mutations or frame-shifting small deletions or insertions (indels) that result in truncation, to transposon insertion, or to DNA rearrangements, which in some cases can delete entire genes or operons.Pseudogenes are particularly abundant in the genomes of recently emerged bacterial pathogens. For example, 337 pseudogenes were identified in Y. pestis strain CO92, representing about 8% of the total gene content.
Pseudogenes are often regarded as exemplars of neutral evolution, the passive loss of functions that are no longer needed. Many metabolic genes of Y. pseudotuberculosis are pseudogenes in Y. pestis, presumably reflecting the fact that Y. pestisalternates between two eukaryotic hosts and no longer needs the metabolic versatility to survive in the environment. However, if a functional gene is somehow detrimental in a new environment (a phenomenon generally referred to as antagonistic pleiotropy), its mutational loss can be positively selected.
In experimental evolution studies, many mutations that eliminate or modify gene function appear to have been beneficial and fixed in the population by positive selection. Often these adaptive null mutations reconfigure metabolic pathways to better fit a new environment. Mutational alteration of central regulatory genes can have especially large fitness effects.
Bubonic plagues are caused by Yersinia pestis. One to seven days after exposure to the bacteria, flu-like symptoms develop. These symptoms include fever, headaches, and vomiting. Swollen and painful lymph nodes occur in the area closest to where the bacteria entered the skin. Occasionally, the swollen lymph nodes may break open. If a medical anthropologist could go back in time, he would contribute to the knowing of the disease’s symptoms and treatments. Since this disease is caused by bacteria, he may suggest use of specific antibiotics to kill the bacteria and revive an individual’s health to normal.
If there were any stigma surrounding this disease the anthropologist would collect information on what fatal circumstances the disease lead to when there was no cure available. Also, he would notice the treatment the person gets form his relatives as well as other dwellers of the area on having infected with this disease. He would also analyze the way in which doctors treated the patient as compared to present scenarios and the amount of advancement in technology that we are enjoying today that were seemed too farfetched in the ancient times.
A medical anthropologist would have been very helpful in many ways like as mentioned earlier he might be able to suggest the use of antibiotics for the killing of bacteria which would not allow any further spreading of the disease and the person may recover in a considerable time period. Also, he might suggest some precautions to prevent the disease and also to vaccinate the children to prevent the disease from infecting the person. He may also be able to notify some do’s and dont’s which might actually help eradicate the disease in the coming years like small pox.
Medical history
- https://www.cprcertified.com/medical-history-the-black-deathinterventionsh/
- http://broughttolife.sciencemuseum.org.uk/broughttolife/themes/publichealth/blackdeathBarker, Sheila. “Poussin, Plague, and Early Modern Medicine.” Art Bulletin, vol. 86, no. 4, Dec. 2004, pp. 659–689. EBSCOhost, doi:10.2307/4134458
