Category: Black Death

Historiographical Essay about the Black Death

The Black Death started in Asia and quickly spread through to Europe while and after it was spreading/had spread it left many horrible consequences for the both the long and short term but the Black Death also left quite a few good changes in the short and long term specifically in the long term. Three consequences that the Black Death left are in the long term people who lived after the Black Death lived longer and healthier lives, in the short term the cost of labour increased so workers could get better pay and in the long term medicines improved.

One of the long term benefits of the Black Death were people lived longer and had healthier lives. The evidence to support this is a study done dug up the bodies of people who lived before, during and after the Black Death (University of Carolina 2014). This study found that after the Black Death people were more commonly reaching ages like 70-80 years and a showed hardiness towards disease. This also made a huge difference in the genetic makeup of the populace as the people who survived the Black Death usually had a specific gene/s that helped them. Also the study found that people were hardier because the Black Death acted as a force of natural selection weeding out those who were weak and frail and leaving those who were healthy and strong to breed therefore making the populace healthier and helping them to live longer.

One of the short term benefits of the Black Plague was a decrease in available labourers. The mass death from the Black Death helped peasants and serfs to get better wages and treatment as the lords had to fight for their work (msh.Council.org 2020). The scarcity of available workers lead to increase in wages and better treatment as peasants found that they could chose not to do a job because its dangerous. They could move to another lord for better pay and treatment, the lords that didn’t want to give their workers better quality conditions soon found that other lords were more than happy to take their worker from them and their workers were all to happy to leave them. This all lead to workers being treated better than they were before the Black Death.

One of the long term benefits of the Black Death was how medicine improved with the development of the Black Death. Medicine at the time of the Black Death was all forms considered mostly quackery and religious healing. The Black Death forced medicine to improve and create treatments that actually healed people. There was a study (Wayne State University 2010) where they looked at the future of medicine after the Black Death. This study points out that the Black Death did in fact reveal some very disastrous short comings and how the Black Death prompted physicians of the time to focus more on the practice of medicine. The study also points out that because of the Black Death universities started teaching the anatomy of the human body to their medical students. The Black Death caused the medical community and its practitioners to improve drastically for the better.

Black Death: Unveiling the Deadly History and Pathogenesis of the Plague

Introduction

Throughout history, there have been many pathogens that are well-known. One of the best-known pathogens is Yersinia Pestis (Y. pestis), more commonly known as the Plague. There are three basic forms of Plague: bubonic, septicemic, and pneumonic. Each form has similar symptoms with small variations, and the mortality rates vary.

Y. Pestis Pathogenesis

The Y. pestis pathogen is a coccobacillus that, when stained with Giemsa, Gram, Wayson’s, or Wright, is a gram-negative pathogen. Y. pestis looks like a safety pin, which makes it easy to identify. It comes from the Enterobacteriaceae family. Y. pestis must be contained in blood if it is to survive. Y. pestis is usually transferred from an oriental rat flea, but it can be transmitted by rats. When the Y. pestis bacteria enters the flea, it backs up the flea’s digestive system. This causes the flea to feel hungry, and it feeds on humans. When it does this, the bacteria is then transferred to the human. While in the flea, the outer layer of the pathogen is lost. Once in the human host, the immune system kills almost all the organisms by polymorphonuclear leukocytes. The tissue macrophages take a few of the bacilli, but they can not kill the Y. pestis. They, therefore, can not create the correct antibodies to fight off the bacteria.

The Y. pestis then spreads to the lymph system and quickly infects them. Many of the symptoms mimic the common flu, which makes it hard to diagnose. In Bubonic Plague, symptoms include high fever, general malaise, buboes (enlarged lymph nodes, usually in groin or neck areas), pain and tenderness in lymph node areas, septicemia, shock, convulsions, necrosis due to hemorrhagic changes, and cyanosis (why they call plague “black death”). Pneumonic Plague has the same symptoms with the inclusion of the lungs turning to liquid and causing the infected individual to cough up the lungs. Septicemic is the deadliest of these three due to it not only having the symptoms of both bubonic and pneumonic Plague, but the body loses the ability to clot. This means that the victim will bleed from all their orifices. (Chamberlain, N. R., & KCOM).

Yersinia Pestis throughout history

There have been three pandemics that have been the most devastating throughout history. The first pandemic lasted from approximately the 6th to 8th AD; this was named the Justinian Plague. The primary outbreak was located in the Mediterranean and eastern areas of the Roman Empire. It killed an estimated 25-50 million people, but that number could be higher. Similar to the outbreaks that followed, this pandemic is attributed to trade routes and changes in climate. The combination of these two factors is attributed to a heightened rat and flea population and an increase in poverty (Horgan, 2015). The second is more commonly known as the Black Plague, which ended the Dark Age. This one lasted from approximately the 14th – 15th century AD.

There are many controversies as to the exact number of people that it killed. They range from 25% to 60% of the European population. This is because the accounts differ between experts, and many are on the more conservative side of things. The last pandemic started in China in the 1860s and lasted until about the early 1900s, and it killed about 10 million people. This outbreak was transported then to the United States, which allowed for other species of animals to carry the disease. These include but are not limited to, squirrels, prairie dogs, chipmunks, and voles. Within the last five years, there have been more recent outbreaks in Madagascar, Africa, and South America. (Centers for Disease Control and Prevention -CDC 2015)

Conclusion

Yersinia Pestis is one of the deadliest pathogens there is. During recorded history, Y. pestis has been responsible for some of the most devastating losses of the human population. Y. pestis is a pathogen that can never really be eradicated if there is poverty and unclean practices. The number of deaths has decreased thanks to the discovery of antibiotics. This is solely dependent on whether the correct form is correctly identified so the antibiotic can be administered in a timely manner.

References

1. Chamberlain, N. R., & KCOM. (n.d.). Yersinia pestis. Retrieved from http://www.kcom.edu/faculty/chamberlain/Website/lectures/lecture/plague.htm
2. Centers for Disease Control and Prevention – CDC. (2015). Plague. Retrieved from https://www.cdc.gov/plague/history/index.html
3. Horgan, J. (2015). Pandemic: The Black Death. History Extra. Retrieved from https://www.historyextra.com/period/medieval/pandemic-black-death/

The Echoes of History: Analyzing Epidemics (Black Death Plague), Then and Now

Abstract

Preceding medical and biological research suppressed historic domestic and worldwide pandemics, but is modern society confident in the anterior brand of resilience? The World Health Organization (WHO) publicized an assertion that specified the potential of an unidentified infection as inevitable as opposed to probable, which evokes the process of procuring remedies as an endless quest and a common worldwide priority (Galsper, 2020). Glasper (2020) further suggested the modern-day spread of epidemics is conclusively associated with international travelers or intercontinental migrations.

However, politics and accountability seemingly infringe on the desired level of unison to combat global pandemics. American government suffers bipartisan accords, and lawmakers struggle with government and state authority to regulate threats of pandemics (Klain, 2018). Globally, culpability encumbers public safety in an effort to save economic desires for the perspective country. Experts who conduct investigative research to curb epidemics are confronted with the two main topics of this narration: research resolution for perseverance and the fluctuation of politics.

Epidemics; Trending Analysis

Viruses such as the Bubonic Plague, smallpox, Severe Acute Respiratory Syndrome (SARS), and Avian Influenza (Bird Flu) are just a few that have plagued populations for generations on a global scale, claiming millions of lives. The existence of pandemics dates back to the prehistoric age that still afflicts havoc in our current society. Infectious diseases that manifest into epidemics are the leading cause of death in human history (Mead, 2019).

Although widespread viruses prove to be deadly, each disease substantiates different levels of lethal potency. The correlation between the Bubonic Plague and smallpox is both viruses are substantially deadly, but the foundations of the plagues are dissimilar. The Bubonic Plague confirmed a mortality rate of 80%, and the smallpox outbreak verified a mortality rate of 30% (Mead, 2019). Paul Mead (2019), Chief of the Bacterial Diseases Branch of the Center for Disease Control, simulated that pox is caused by a virus, and humans are determined to be the exclusive host of the illness, whereas the spread of the Bubonic Plague generated from the bite of a flea or another host. The conclusion of this study proves the onset of any epidemic is the key to reaching a plausible containment and vaccination. However, medical research and development to curb the effects of a disease is confronted by a social aspect and perspective that sways politicians, which impedes the process (Klain, 2018).

Bubonic Plague

Among a variety of viruses, the Bubonic Plague and smallpox will be examined as a focal point. The Bubonic Plague overwhelmed humankind on a global scale in the mid-1300s. This epidemic was generated in Europe and Asia in 1347 when ships reached a destination in Sicily after crossing the Dead Sea (Dols, 2019). Dols (2019) narrated half of the occupants and workers aboard this ship perished from an illness, and the other half presented unknown symptoms: black boils with oozing pus accompanied by other complications. Despite the need for medical attention, the Sicilian government ordered the ships to leave the harbor. Despite the reaction of the Sicilian government to turn the infected ship away, the plague claimed the lives of 20 million people in Europe, which was later identified as the Bubonic Plague.

According to historical evidence, Europeans learned of the pestilence before the plague ship arrived in the Sicilian Harbor (Mulhall, 2019). Mulhall (2019) specified that Europeans heard of the disease spreading across the trade routes in China, India, Syria, and Egypt. The Bubonic Plague was later termed the “Black Death” Plague and fashioned the alternative title from the ship that crossed the Black Sea into the Sicilian port. The Black Death Plague was deemed highly contagious, which caused widespread infections. In addition to ‘oozing boils,’ other symptoms were fever, chills, vomiting accompanied by diarrhea, and body aches. All of these are attributed to blood and lung infections that result in death when untreated (Mulhall, 2019).

This epidemic was generated from insects and rodents that spread to humans. Once the human was infected, the disease was able to spread to another by simply breathing the same air as the infected individual (Dol, 2019). Politicians warded all imports that impacted local economies, and citizens ultimately suffered the loss of employment. Experts conducting the research urged this type of isolation to minimize the spread, but locals revolted and ultimately rescinded precautions, causing more devastation (Malhall, 2019).

Small Pox

The smallpox epidemic predates the Bubonic Plague, and historians asserted this plague began to eradicate humans 12,000 years ago. The manifestation of smallpox resulted in a highly contagious disease that killed an estimated 7 million people (Meyer et al., 2020). This epidemic was generated in Athens in 430 B.C. and imminently infected Egypt by 1570 B.C. The similarities between the Bubonic Plague and Small are that both developed pus-filled legions that eventually affected the bloodstream and lungs, causing death. Smallpox ultimately caused disfiguration and blindness before inflicting death if untreated.

However, the difference is the onset of the diseases. Smallpox is proven to spread from human to human as opposed to air contagions, and there is no evidence of spread through insects or animals (Meyer et al., 2020). Therefore, humans are the sole host of this plague, but it is believed that healed patients were not susceptible once immunity was established. Therefore, injecting small amounts of the disease would create immunity, but it was not a full-proof vaccination (Meyer et al., 2020). The notion was capitalized in England in 1796, when indirect exposure proved to have a lasting effect (Eto et al., 2019). The WHO finally eradicated the smallpox epidemic in 1980, and the search for a vaccination took centuries to resolve.

Smallpox is blamed for being used as a biological weapon during the French and Indian War in 1763. Historians recalled the British Commanders inflicted the disease against their rivals and reduced the Native American population by 90 percent (Meyer et al., 2020). Rival countries would target opposing rulers with the disease, which would eventually spread throughout the contending regime (Meyer et al., 2020). Despite the deadly aftermath of the smallpox epidemic, this disease was a driving force for political gain, and medical urgencies were suppressed.

Conclusion

Historically, epidemics proved to have an impact on international cultures. Despite the death toll, diseases tore down and built many countries depending on the perspective. However, the threat of plagues continues to be a looming concern. In contrast, the Bubonic Plague and smallpox inflicted international devastation that changed history. Did the effects of past epidemics invoke current lessons to curb looming epidemics? Depending on the perspective amid the COVID-19 infection, the same trepidations experienced centuries ago still remain.

To limit the Black Death and Small Pox epidemics, the source of the disease was pursued much like the intentions of current experts to get rid of the COVID-19 virus. Moreover, locals demand leaders lift restrictions and return to work despite the threat of an active epidemic, similar to the locals reacting to the Bubonic Plague. In addition to the domestic concerns, COVID-19 was generated in another country before infecting America and likewise to the forenamed plagues. This narrative is not to point out blame but to highlight the trending facts of past epidemics, proving history actually repeats itself.

Research and development derive around the onset of the infection; lawmakers and leaders utilize the vulnerability for political gain, and governments ultimately make efforts to curb the pandemic. Economies suffer, and panic strikes the populations. Despite the innovation, the study to curb a pandemic is persistent with past plagues, and the reaction of the populous and politicians presents a comparable trend to the old.

References

1. Dols, M. W. (2019). The black death in the Middle East. Princeton University Press. Retrieved from:https://books.google.com/booksl=en&lr=&id=F22DDwAAQBAJ&oi=fnd&pg=PP1&dq=bubonic+plague&ots=nm7slhXLu&sig=aX4rayfDoEPUbhn3AIg8xOlaojg#v=onepage&q=bubonic%20plague&f=false.
2. Eto, A., Fujita, M., Nishiyama, Y., Saito, T., Molina, D. M., Morikawa, S. & Kanatani, Y. (2019). Profiling of the antibody response to attenuated LC16m8 smallpox vaccine using protein array analysis. Vaccine, 37(44), 6588-6593. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0264410X19311946.
3. Glasper, A. (2020). Potential global pandemics: the role of the WHO and other public health bodies. British Journal of Nursing, 29(5), 322–323. Retrieved from https://doi.org/10.12968/bjon.2020.29.5.322.
4. Klain, R. (2018). Politics and pandemics. New England Journal of Medicine, 379(23), 2191–2193. Retrieved from: https://www.nejm.org/doi/full/10.1056/NEJMp1813905.
5. Mead, P. (2019). Epidemics of plague past, present, and future. The Lancet Infectious Diseases, 19(5), 459–460. Retrieved from: https://doi.org/10.1016/S1473-3099(18)30794–1.
6. Meyer, H., Ehmann, R., & Smith, G. L. (2020). Smallpox in the Post-Eradication Era. Viruses, 12(2), 138. Retrieved from: https://www.mdpi.com/1999-4915/12/2/138/htm.
7. Mulhall, J. (2019). Plague before the Pandemics: The Greek Medical Evidence for Bubonic Plague before the Sixth Century. Bulletin of the History of Medicine, 93(2), 151–179. Retrieved from: https://muse.jhu.edu/article/729236.

Unveiling the Horror: The Black Death and its Catastrophic Impact on Europe

Introduction

“The Black Death”, “The Great Mortality”, “The Bubonic Plague”, all of these refer to a time in history where disease followed by death were almost inevitable. Disease was covering Europe and killing its people without hesitation; death rates were unbelievably high.

The Ravaging Plague

It is important to realize that about 1/3 of the world’s population was lost during this awful time and the people, at this time, did not understand the plague. They had no idea what was causing this sickness and even thought that slaughtering cats could be the answer. The medical knowledge at this time also made it harder to end the plague due to the limited knowledge they possessed. The doctors of the plague knew so little that they believed they could not be infected with this disease. All of these factors led to the spreading of the disease and mass death in Europe. The Black Death began with tiny creatures that are usually completely ignored by humans, fleas. The bacterium, Y pestis, inhabit the digestive tract of these insects and, because of their small size, the disease spread like wild fire. The disease originally resided in rats, and then rat fleas would suck the blood of the rats, becoming infected themselves.

After a single flea bite, a human would die within a week or less; the quickness of this disease also caused the death rates to climb at exponential rates. The infected human would begin to cough and ache, followed by the appearance of large black boils.1 Next the person would begin to throw up blood and could then have high fevers causing hallucinations.1 Between humans, exposure to body fluid was the only thing needed to become infected and this meant that a simple cough, spreading saliva, could infect anyone nearby.

Between 1347 and 1352, 25 million people were infected and killed by the Black Death.1 Although this seems to be an unimaginable number, the amount of death rates in Justinian’s Plague could have been anywhere from 25 million to 50 million. Because the Black Death caused so many people to die, many jobs were open for those who were left. Peasants were given an opportunity to take on higher paying jobs and possibly do better for themselves. The government, however, began to put laws in place that caused these peasants to not make the money they deserved. Laws and limitations like these are what caused the English Revolt of 1381. The peasants did not believe that this was fair treatment, and so they fought for more rights.

Religious Disruption and Quality

The Ciompi Revolt began over the desire of more rights by the merchant class, which of course was denied by the government. These people rebelled and fought for the rights they felt they deserved. These brave men do in fact take over the oligarchy, however, they were not able to continually keep this power. Because the plague was taking out large masses of people at once, priests were becoming few and far between. Priests were extremely important to have around, however, and therefore the requirements for becoming a priest were done away with.

People of all ages and backgrounds could be priest now and this greatly lower the quality of these priests. One had to have no background of the church and was not required to possess any particular amount of religious knowledge to become a priest. They simply had not been trained and did not know enough about the religion to be a leader in religious affairs.

Conclusion

Even the quality of services for the dead were lowered and the rituals were all but cut out completely. The rate at which people were dying did not allow time for a full ceremony, but only for the bodies to be placed in a graveyard with the other victims of the plague. This plague was a gruesome time for all of Europe and many places suffered massive losses. As previously written, nearly 25 million people died in just under 5 years due to this death ridden Bubonic Plague. The rate at which this disease spread made the situation even worse because doctors could not isolate the infected fast enough. The Bubonic Plague was a negatively extraordinary disease that killed millions in Europe and one can only pray it never appears again.

References

1. “The Black Death: A Personal History” by John Hatcher
2. “The Great Mortality: An Intimate History of the Black Death, the Most Devastating Plague of All Time” by John Kelly
3. “The Black Death: Natural and Human Disaster in Medieval Europe” by Robert S. Gottfried

Unlocking the Secrets of the Black Death: Mysteries of Yersinia Pestis

Introduction

The Plague is caused by the bacterium Yersinia pestis. There are three extremely well-known pandemics; the first well-documented crisis was the Plague of Justinian. The most infamous, with the highest estimated death toll, was the Black Death. Then came the Great Outbreak of London as a result of the migration of the bacteria. Yersinia pestis is the lethal bacterium known for killing an estimated 70-200 million people in Europe, Asia, and Africa during the Black Death. Scientists concluded that even though the Plague originated in Asia, it was likely that the fleas that lived on rats, called Xenopsylla cheopis, transported this disease to the other two continents. The two different types include primary bubonic Plague and septicemic Plague. Plague bacteria are most often transmitted by the bite of an infected flea.

Tracing the Footprints of Death: Historical Pandemics

During plague epizootics, many rodents died, causing hungry fleas to seek other sources of blood. The enzootic cycle was when the Y. pestis was able to circulate at low rates within populations of rodents, mostly undetected because it didn’t produce an outbreak. When the bacteria pass to other species during an epizootic cycle, humans face a greater risk of becoming infected with plague bacteria. People and animals that were near areas where dead infected animals were were at risk of being infected from flea bites. Dogs and cats also plague-infected fleas into homes.

From the teeth of plague victims, scientists have pieced together a family tree of Y. pestis, discovering that the strain from the Justinian Plague was related to, but distinct from, other strains of the Plague. Scientists discovered last year, during the construction of the new cross-rail underground rail link beneath London, recovered DNA of Yersinia pestis from skeletons from the Great Outbreak of London. The DNA was identified by teams of scientists from the Museum of London Archeology (MOLA) and the Max Plank Institute in Germany.

Tooth enamel preserved the genetic information of any bacteria that was circulating in the individual’s bloodstream at the time of death. The bacteria perished shortly after its host did, so the remains posed no risk. Stable isotope analysis of strontium (a highly chemically reactive element) and oxygen in the individuals’ teeth enabled scientists to learn if they were native Londoners or if they moved to the city from elsewhere. Carbon and nitrogen isotopes revealed how much meat, vegetables, and seafood they ate. Microbiome DNA from their teeth helped to further determine which airborne particles and pollutants they ingested in life.

Unlocking the Genetic Secrets: From Ancient Victims to Modern Revelations

Many scientists believed that the Y. pestis could not have been the cause of the Plague because of how mild other Bubonic plagues were in comparison to ancient outbreaks like the Black Death. A team led by Didier Raoult, a microbiologist at the University of the Mediterranean in Marseilles, France, successfully recovered Y. pestis DNA from the teeth of a child and two adults dug up from a fourteenth-century mass burial site in Montpellier. The team identified the bacterium using a sensitive technique called the polymerase chain reaction (PCR) to amplify a portion of a gene from Y. pestis called pla. Proving that the Y. pestis was the bacterium during the plague outbreaks.

Hendrik Poinar, a palaeogeneticist at McMaster University in Hamilton, Canada, who co-led the sequencing efforts, considered drilling into teeth and bones to find Y. pestis DNA but wasn’t satisfied with the available detection tools, which were based on PCR. Next-generation DNA sequencers (machines that read short amounts of DNA) could sequence DNA that had been damaged, spending hundreds of years underground. The sequencers allowed Svante Pääbo, a palaeogeneticist at the Max Planck Institute for Evolutionary Anthropology, and his team to sequence a draft of the Neanderthal genome. However, finding and sequencing ancient pathogens in a human skeleton was extremely difficult. Pääbo and his team developed a technique called targeted capture. Using lab-synthesized DNA, it isolated ancient DNA strands from a bone sample, leaving soil microbes and other sequences behind.

In an experiment published in August of this year, Krause and Poinar’s team used sequences from a contemporary plague strain to find and isolate Y. pestis DNA from the teeth of the buried victims. They then sequenced a short loop of DNA called the pPCP1 plasmid (the plasmid partially responsible for bubonic plague infection in humans).

Their results have convinced most scientists that the bubonic Plague was involved in the Black Death. In their most recent paper1, Poinar and Krause completed the ancient genome and showed that it sits at the root of an evolutionary tree that comprises 17 contemporary strains of Y. pestis. This indicates that the Black Death strain spawned many of the forms of Y. pestis that infect humans today.

Conclusion

Y. pestis seemed to have changed very little over the past 660 years. The genome of the Black Death strain differs from the modern Y. pestis, but each genetic difference is found in at least one contemporary strain. These results contradict the findings of Pionar and Krause as there is no evidence for why the bacterium could suddenly create such a massive outbreak as the Black Death. The team is now looking for other genetic changes that could account for the ferocity of the Black Death, such as rearrangements in the genomes.

References

Black Death in Modern Times: Assessing Spread and Potential Impact

Introduction

The topic that I chose was how the bubonic plague would spread if there was a modern-day pandemic. I chose this exploration because the bubonic plague interests me. I learned in history class about the Black Death, which wiped out around two-thirds of the world’s population during the fourteenth century (Benedictow). I wanted to know if it was possible for the bubonic plague to spread and be fatal to that degree during modern times. I have always been interested in diseases, and this gives me the perfect opportunity to look into something I am interested in. The bubonic plague was spread by fleas that had been infected by Yersinia pestis (Plague). Typically, a person who is infected wouldn’t know for about one to seven days (Plague). This allows the disease to grow and spread in the lymph nodes of the human host’s body, which could go to the lungs and kill the person (Plague). When the host has the pneumonic plague, they can spread it to the people around them. In this exploration, the math that can be used is probability, mainly conditional probability, expected value, and tree diagrams. This math can be used because I will be tracking the spread of the disease from host to host.

Body

Spread Dynamics

The Bubonic Plague is caused by the bacteria Yersinia Pestis, which is transferred by rodents or fleas (Plague). In my exploration, I am saying that there is no way to prevent the plague, such as pest control or a vaccine. Pest control would lessen the chances of fleas and rats being able to be in close proximity to people. The vaccine or other ways of treatment also need to be taken out of the equation because I am just focusing on how fast the plague could spread without those factors. I will be using New Mexico as the place for which I will be infected. New Mexico is one of the common places in the United States where the plague can occur (‘FAQ | Plague | CDC.’).

Rodents carry fleas, which can then be transferred to people. Around 63% of cases of the plague in New Mexico come directly from flea bites (PLAGUE IN NEW MEXICO ). This leaves 37% that come from other sources. The other sources can include fluids from an infected animal, being scratched, and inhaling droplets from an animal or person with pneumonic plague (PLAGUE IN NEW MEXICO ). Mexico has a population of about 2,090,708 people (‘World Population Review’). The equation that represents how many people are affected by rodents in New Mexico is y=(x100)2090708. In this equation, y is the number of people who have a rodent problem, and x is the average percentage of people who have rodent problems. I can use this equation and make a table out of it to see how many people could be affected by rats. The equation is only good when 0X100. This is because there cannot be negative people, and there cannot be more people than there already are.

Potential Impact and Mortality

Having rat problems potentially exposes people to fleas, which can carry the Yersinia Pestis bacteria, which is the cause of the Bubonic Plague. The probability of getting the plague directly from a flea bite is 63% or .63 (PLAGUE IN NEW MEXICO). If someone has a rodent problem, it can be assumed that the fleas will eventually change what they host and jump to other mammals in the household. The probability of getting the plague from anything but a direct flea bite is 37% or .37 (PLAGUE IN NEW MEXICO). A tree diagram can be used to potentially show how a family of four could possibly become infected.

From the diagram, we can see that the probability of all four people getting infected from a flea bite is .15752961. The probability of all four getting infected from anything but a flea bite is .01874161. Most people appear to get the plague from a flea bite rather than by other forms of transmission. For the next part, I will focus on how people could get infected just by getting bitten by fleas.

If the person has a dog or cat, the fleas will use the dog or cat as a host as well as people. The American Veterinary Medical Association states that “New Mexico ranks second in the nation for pet ownership with 67.6 percent of the state’s households owning a pet” (Gerew). The fleas could spread the bacteria from rat to cat or dog to human. Cats and dogs have an average of twenty fleas but can have up to 200 or 300, but 150 is a high amount (“How Many Fleas Can Live on a Cat or Dog?”). Since 300 is the maximum amount of fleas, the denominator for probability has to be 300. So the P(fleas on the cat) = 115 and the P(fleas on the dog)=115.

The probability is 115 because that is what 20300 is reduced to. Since 67.6% of people in New Mexico have pets, we can multiply the total population of New Mexico by .676, which is 67.6% in decimal form. So .6762090708=1413318.608, and since it is not a full person, I will round up; this means that 1413319 people in New Mexico will have pets. Since the average number of fleas on dogs and cats is 20 (“How Many Fleas Can Live on a Cat or Dog?”), This means that there is a 120 chance of a flea jumping onto a human from a dog or cat. With this information, I can make an expected value chart.

The expected value for the future is 143.5 or 2872 when you add the X P(X) column together. In the future, there could be more than 20 fleas on a person at once. I can also use the numbers with fleas and pets to do conditional probability.
PFleas|Has Pets=PFleasPetsPPets
PFleas=120
P(Pets)=.676
P(Fleas Pets)=1695000
PFleas|Has Pets=(169/5000).676
PFleas|Has Pets=.05

There is a 5% that a person will have at least one flea jump onto them given that they have pets. In New Mexico, 33105 species of fleas have been found to carry the Yersinia Pestis bacteria (PLAGUE IN NEW MEXICO). Based on my findings above, I can multiply 5% by the species of fleas ( .0533105=11700 ) to find out the chance of someone getting bitten by a flea that can carry the bacteria, which is a 1.57% chance. Out of the 1413319 people who have pets, 1.57% will get bitten by a flea that carries the bacteria; this is 141331911700=22209.29857, and it has to be rounded up to 22210.
In relation to rodents with fleas, 29% of people will have a rodent problem (“Of Mice and Men”). Using the earlier equation, y=(x100)2090708, I can plug in 29 as X. (29100)2090708=606305.32. There would be 606306 people in New Mexico that would have rodents in their homes. On average, each rat will carry 4.1 fleas (Frye); there is a 14 chance of the fleas jumping into people. Conditional probability can also be used here to find the percentage of people who will get bitten by fleas, given that they have a rodent problem.

PFleas|Has Rodents=PFleasRodentsPRodents
PFleas=14
P(Rodents)=.29
P(Fleas Rodents)=29400
PFleas|Has Rodents=(29/400).29
PFleas|Has Rodents=.25

Given the calculations, 25% of these people who have rodent problems will have been bitten by a flea. Since 33105 species carry the bacteria, I can multiply the number of people who have rodents by 25%, then multiply that number by 33105 to find the number of people who could get the plague just from having rodent problems.

606306.25=151576.5rounded up, that is 151577 people who will get bitten by a flea if they have a rodent problem. I can then take the 151577 people and multiply that by the number of fleas that carry the bacteria to find the number of people who will have the bacteria. 15157733105=47638.48571rounded up, this is 47639 people. Adding this number to the people who have pets and could get infected, 47639+22210=69849 people will get infected directly from a flea bite. The bubonic plague, if left untreated, is deadly about 50% of the time (PLAGUE IN NEW MEXICO). Taking the number of people infected by flea bites and multiplying by 50% or .50, 69849.50=34924.5rounded up is 34925 people will die of the plague just from getting bitten by a flea if they have a rodent problem or pets.

Conclusion

The Bubonic Plague is notorious for having been the cause of death for millions in Europe when an outbreak occurred in the fourteenth century (Benedictow). I decided that I wanted to find out whether or not the plague could be that deadly in modern times. To do this, I used New Mexico and used probability to find out the numbers. I used a tree diagram to show the different ways a small family could get the plague and the probability of each way; I used expected value as well as conditional probability. From my calculations, I have found out that the bubonic plague could come back, just not as deadly as it once had been. Only 34,925 people out of the 2,090,708 people in New Mexico would die from the bubonic plague; this is 1.67% of the population, which is not close to the 60% of the population that died in the fourteenth century (Benedictow). In conclusion, the bubonic plague currently will never be as bad as it was in the fourteenth century.

References

1. Benedictow, Ole Jørgen. “The Black Death: The Greatest Catastrophe Ever.” History Today, vol. 63, no. 3, 2013, pp. 2-8.
2. Gerew, Sam. “New Mexico Ranks Second in the Nation for Pet Ownership.” KVIA, 4 Nov. 2019, https://kvia.com/news/new-mexico/2019/11/04/new-mexico-ranks-second-in-the-nation-for-pet-ownership/.
3. Frye, Matt. “Fleas on Rats and Cats.” Pest Control Daily, 18 Feb. 2022, https://pestcontroldaily.com/fleas-on-rats-cats/.
4. “How Many Fleas Can Live on a Cat or Dog?” PetMD, 11 Mar. 2020, https://www.petmd.com/dog/general-health/how-many-fleas-can-live-cat-or-dog.
5. “PLAGUE IN NEW MEXICO.” New Mexico Department of Health, https://www.nmhealth.org/about/erd/ideb/zdp/plg/.
6. “World Population Review.” World Population Review, https://worldpopulationreview.com/states.