Reflective Essay

I learned so much in Epidemics and Society and it was the most interesting class I ever took because we learned all about the diseases that have changed our world and society.  One of the deadliest diseases was the Black Death or Bubonic Plague.  It ravaged Europe and in the end an estimated 75 million people died from their symptoms.  It took several centuries for the world’s population to recover from the devastation of the plague, but some social changes were permanent.  The disease existed in two varieties, one contracted by insect bite and another airborne.  In both cases, victims rarely lasted more than three to four days between initial infection and death, a period of intense fever and vomiting during which their lymph nodes swelled uncontrollably up to the size of an orange or tennis ball and eventually burst.  The plague bacteria had been started for hundreds of years before incubating again in the 1320s in the Gobi Desert of Asia, from which it spread quickly in the blood of fleas. It followed in the medieval trade routes from China, through Central Asia and Turkey. The plague reached Italy in 1347 aboard a merchant ship whose crew had already died or been infected by the time it reached port. The Black Death ravaged the continent for three years before it continued on into Russia, killing one-third to one-half of the entire population.

The origin of smallpox is unknown.  Smallpox is thought to be around the 3^rd century BCE based on a rash found on three mummies.  It first appeared in China in the 4^th Century CE and early written descriptions also appeared in India in the 7^th century and in Asia Minor in the 10^th century. Smallpox was a devastating disease.  On average, 3 out of every 10 people who got it died.  Those who survived were usually left with scars and they were sometimes severe.  One of the first methods for controlling the spread of smallpox was the use of variolation.  Variolation is the process by which material from smallpox sores was given to people who never had smallpox.  This was done either by scratching the material into the arm or inhaling it through the nose. With both types of variolation, people usually went on to develop the symptoms associated with smallpox, such as fever and a rash.  However, fewer people died from variolation than if they had acquired smallpox naturally.  The basis for vaccination began in 1796 and doctors conducted experiments on cows with milkmaids.  After that, vaccination became widely accepted and gradually replaced the practice of variolation.  At some point in the 1800s, the virus used to make the smallpox vaccine changed from cowpox to vaccinia virus.  Those who received this treatment contracted a mild form of the disease, developing a lifelong immunity.

Today, we have vaccines that help us prevent these deadly diseases that can make us really sick.  Without these vaccines we would be getting them and making us sick.  The infectious diseases have changed our world and society so much that we have invented vaccines and all kinds of medicine to prevent them.  However, we still have the influenza virus that goes around in our country today.  People can still get the disease even though they get the shot or spray up in their nose.  I’mglad that I was not born at the time when these diseases were going on and if I was born at the time I would have been miserable.  I”m blessed to be living in the US and not Europe or Africa because that’s where most of the diseases come from.  Examples would be Ebola and the Bubonic Plague.

Since the 1980s, there has been a lot of debate around the origin of HIV.  HIV is a type of lentvirus, which means it attacks the immune system.  In a similar way, the SIV virus attacks the immune systems of monkeys and apes.  Research found that HIV related to SIV and there are many similarities between the two viruses.  HIV-1 is closely related to a strain of SIV found in chimpanzees and HIV-2 is closely related to a strain of SIV found in mangabeys.  In 1999, a strain of SIV was found in a chimpanzee that was almost identical to HIV in humans.  The researchers who discovered this connection concluded that it proved chimpanzees were the source of HIV and that the virus had crossed species from chimps to humans.  The same scientists then conducted more research into how SIV could have developed in the chimps.  They discovered that the chimps had hunted and eaten 2 smaller species of monkeys and became infected with 2 different strains of SIV.

Studies of some of the earliest known samples of HIV provide clues about when it first appeared in humans and how it evolved.  The most studied strain of HIV is HIV-1 Group M, which is the strain that has spread throughout the world and is responsible for the vast majority of HIV infections today.

Zoonotic pathogens are twice as likely to be associated with newly discovered, emerging, human illnesses.  Of all the infectious agents that humans, approximately 60% are zoonotic.  The 1999 outbreak of West Nile virus in New York City was a perfect illustration of the challenges societies face in addressing zoonotic diseases.  There have been many other emerging zoonotic disease outbreaks, including the Nipah virus outbreak in Malaysia in 1998-1999, the severe acute respiratory syndrome (SARS) outbreak in 2003 and most recently, the avian influenza outbreak that is spreading throughout Asia, Europe and Africa.  Many of the agents of bioterrorism are zoonotic in origin.  In fact, five of the top six “category A” disease agents designated as potential bioterror threats by the United States Centers for Disease Control and Prevention (CDC) are zoonoses.  Reasons for the emergence of these zoonotic disease outbreaks are multiple human population pressures, intensive agricultural pressures, intensive agricultural practices, consumption of bush meat, importing and dumping of used tires that serve as reservoirs for mosquito breeding,  air travel and a global trade in exotic animals.  Since scientists have identified less than 1% of the viruses on the planet, it should be anticipated that many more zoonotic viral pathogens will emerge.

Tuberculosis is a chronic or acute infection caused by bacteria called Mycrobacterium tuberculosis. Tuberculosis mainly affects the lungs but can also attack kidneys, bones, lymph nodes and brain.  When localized to the lungs, tuberculosis can run an acute course, causing extensive destruction in a few months so-called galloping consumption.  It can also wax and wane with periods of remission mistaken in some cases for chronic bronchitis with spitting up of blood.  Tuberculosis can affect organs other than the lungs, including the intestine and larynx, sometimes the lymph nodes in the neck are affected, producing a swelling called scrofula.  Modern strains of Mycobacterium tuberculosis appear to have originated from a common ancestor about 20,000-15,000 years ago.  By Laennec’s era, tuberculosis had surged across Europe in an epidemic tsunami.  Death rates in London, Stockholm, and Hamburg approached 800-1000/100,000year at that time.

The potato was important because the Irish population grew from 3.5 to 8 million between 1700 and 1840.  Economic relationships between Ireland and England were factors in the impending disaster such as increasing population, exploitation by land owners, enforced exports of food crops to England, poor housing conditions and low standard of living, dependence on potato for food.  High field crop producing a very healthy food with little labor investment.  Irish were potato people and were remarkable healthy with potatoes as appetizer, dinner and dessert. Many Irish survived on milk and potatoes alone and the two together provide all essential nutrients while others subsided on potatoes and water, or a little cabbage and salt.  By the early 1840s, almost one-half of the Irish population had become entirely dependent upon the potato, specifically on just one or two high-yielding varieties.  From 1845 to 1852, the Irish potato production was ravaged by blight.  Blight accounted for crop loss of anywhere from one third to one half of all acreages planted in 1845.  Three quarters of the crop was lost 1846.  Seed potatoes were scarce for many years following these two devastating years, limiting recovery.  The result of the potato blight was mass starvation, disease, and emigration in Ireland between 1845 and 1852.  It was also called Irish Potato Famine since 2/5 of population was solely reliant on the cheap potato crop.  1 million or more died and emigrated from Ireland between 1846 and 1851, mainly to North America.

Phytophthora infestans was the pathogen responsible for the Irish Potato Famine.  The disease led to widespread famine, and nearly all of the few potatoes available were eaten, causing shortages of seed potatoes that ensured starvation would continue for nearly a decade,  Ultimately, over one million people died, and another million emigrated to escape the disaster, causing Ireland’s population to fall by roughly 25 percent.  The island has still not reached its pre-famine population levels today.  Currently, P. infestans is distributed worldwide, with the vast majority comprised of the destructive strain US-1.  Most of the other strains of P. infestans occur only in Mexico’s Toluca Valley, where wild potato varieties are indigenous, so scientists long believed that US-1 had been responsible for the 1840s famine.

Smallpox was a major killer of children and babies.  In some ancient cultures, smallpox was such a major killer of infants that custom forbade the naming of a newborn until the infant had caught the disease and proved it would survive.  Smallpox changed the course of history and it has been involved with war, exploration, and migration.  Repeated epidemics swept across continents decimating populations and killing hundreds of millions of people over the centuries.  In the 20th century alone, it killed 300,000,000 people.  Freedom from smallpox was declared in Bangladesh in December, 1977 when a WHO International Commission officially certified that smallpox had been eradicated from that country.

Humans likely acquired smallpox from one of the pox-like diseases of domesticated animals in the earliest concentrated agricultural settlements of Asia or Africa when humans began to maintain herds of livestock.  Observations of typical smallpox skin rashes on Egyptian mummies dating 1100 to 1580 BCE; theories that ancient Egypt was an early smallpox endemic region.  Historical and medical records from Asia: evidence of smallpox-like disease ancient China and India.  Earliest unmistakable description of endemic smallpox first appears in 4th century CE China, 7th century CE India and Mediterranean, and 10th century CE SW Asia.  These earlier Asian descriptions suggest that pandemic smallpox originated in East Asia.  Smallpox can be transmissioned in many ways such as face to face contact, infected body fluids, scabs, contaminated objects and airborne spread.  Spread of smallpox was spread through wars, movement of populations, trade routes and caravans, slave trade.  Vaccine became safer in 1891 when Monckton Copeman demonstrated germicidal effects of glycerin on vaccine.  In 1939, researcher Allan Watt Downie showed that the smallpox vaccines being used in the 20th century and cowpox virus were not the same, but were immunologically related.  At that point, the name “vaccinia” was used for the virus in smallpox vaccine.  Vaccine potency and efficacy prior to the invention of refrigerated methods of transportation was unreliable.  The vaccine would be rendered impotent by heat and sunlight, and the method of drying samples on quills and shipping them to countries in need often resulted in an active vaccine.

Syphilis is caused by an organism called Treponema Pallidum.  The four species that cause treponemal diseases such as syphilis and nonvenereal treponemal diseases are bejel, pinta, and yaws.  The disease is acquired by close sexual contact.  Initial lesions are usually on the labia, vagina, or cervix, shaft or glans of penis; usually single lesions; can occur elsewhere.  It gains access to host’s blood and lymph systems through tissue and mucous membranes.  It can be transmitted to a fetus by transplacental passage (results in congenital syphilis).  Signs and symptoms vary depending on the stage (primary, secondary, latent, and tertiary).  Each of the different stages have different symptoms with chancres, rash which frequently involves the palms of the hands and soles of the feet and gummas.

The Tuskegee Syphilis Study was designed to determine the natural course of untreated latent syphilis in some 400 African American men in Tuskegee, Macon County, Alabama.  The subjects were recruited with misleading promises of “special free treatment,” which were spinal taps done without anesthesia to study the neurological effects of syphilis, and they were enrolled without their informed consent.

The subjects received heavy metals therapy, standard treatment in 1932, but were denied antibiotic therapy when it became clear in the 1940s that penicillin was a safe and effective treatment for the disease.  When penicillin became widely available by the early 1950s as the preferred treatment for syphilis, this therapy was again withheld.  On several occasions, the USPHS actually sought to prevent treatment. The first published report of the study appeared in 1936, with subsequent papers issued every four to six years until the early 1970s.  In l969, a committee at the federally operated Center for Disease Control decided the study should continue.  Only in 1972, when accounts of the study first appeared in the national press, did the Department of Health, Education and Welfare (HEW) halt the experiment. At that time, 74 of the test subjects were still alive; at least 28, but perhaps more than 100, had died directly from advanced syphilis.  An investigatory panel appointed by HEW in August 1972 found the study “ethically unjustified” and argued that penicillin should have been provided to the men.  As a result, the National Research Act, passed in 1974, mandated that all federally funded proposed research with human subjects be approved by an institutional review board (IRB).  By 1992, final payments of approximately $40,000 were made to survivors under an agreement settling the class action lawsuit brought on behalf of the Tuskegee Study subjects.  President Clinton publicly apologized on behalf of the federal government to the handful of study survivors in April 1997.

Several major ethical issues involving human research subjects need to be studied further.  The first major ethical issue to be considered is informed consent, which refers to telling potential research participants about all aspects of the research that might reasonably influence their decision to participate. A major unresolved concern is exactly how far researchers’ obligations extend to research subjects. Another concern has to do with the possibility that a person might feel pressured to agree or might not understand precisely what he or she is agreeing to.  The investigators took advantage of a deprived socioeconomic situation in which the participants had experienced low levels of care.  The contacts were with doctors and nurses who were seen as authority figures. The USPHS practiced deception in recruiting subjects for the study.  It was never explained to the subjects that the survey was designed to detect syphilis.  The term “bad blood,” which was a local colloquialism for everything from anemia to leukemia, was used by the doctors and never defined for the subjects.  Subjects were never told they had syphilis, the course of the disease, or treatment. The second major ethical issue is the withholding of treatment for research purposes.  This is the gravest charge against the study.  Patient welfare was consistently overlooked, although there have been multiple attempts to justify why penicillin treatment was withheld.  Some physicians felt that repair of existing damage would be minimal, and others felt that the damage that could result from reactions to the penicillin therapy, including fever, angina, and ruptured blood vessels, would outweigh its benefits.  At the time of the Tuskegee Study, no data was available on the efficiency of penicillin treatment in late syphilis, and short­ and long ­term toxic effects of drugs had not been well documented.  In short, when the study was evaluated periodically, researchers judged that the benefits of non treatment outweighed the benefits of treatment.  Moreover, the subjects were never given a choice about continuing in the study once penicillin had become available; in fact, they were prevented from getting treatment.

The decision was made based on several factors, including the state of the disease, assumptions about the participants, and fear related to the danger of lethal reactions if the men were to receive penicillin.  Several other ethical issues surrounded the study.  First, Alabama had passed a law in 1927 that required  the reporting and treatment of several diseases, including syphilis, by medical personnel.  The USPHS ignored the state law, choosing to disregard the impact of untreated syphilis on wives of the married men who were subjects.  Second, accurate records were not kept.  The number of subjects who died from syphilis was never known.  The number of survivors was estimated to be between 76 and 111, and the number of dying was estimated between 28 and 101. Third, beliefs within the medical profession about the nature of African Americans, sexual behavior, and disease clouded the study.  As a result, the health of an entire community was jeopardized by leaving a communicable disease untreated. Fourth, although no comprehensive report was ever published, the study was reported in medical journals for nearly 40 years without protest from anyone in the medical community.  The investigating doctors never questioned the morality of the study.  Also, HEW had no mechanism for periodic reassessment of the ethics and scientific values of the studies being conducted. The subjects received heavy metals therapy, standard treatment in 1932, but were denied antibiotic therapy when it became clear in the 1940s that penicillin was a safe and effective treatment for the disease.  When penicillin became widely available by the early 1950s as the preferred treatment for syphilis, this therapy was again withheld. On several occasions, the USPHS actually sought to prevent treatment.

The bubonic plague is an ancient disease caused by fleas that carry Yersinia pestis, the bacterial cause of the plague to a common black or brown house rat (also called a ship rat or plague rat).  When a rat dies, fleas leave to find another living rat and if there is no rat a human will be another host.  The origin of the plague thought to have originated from Himalayan borderlands between India and China.  It was generally believed that plague escaped its Asian confines in the 6th century and marched westward.  The Justinian plague lasted from 542 CE to around the middle of the 8th century.  The buboes are tell-tale signs of the plague and lymph nodes swell to the size of an egg or even an orange.  Infection can be septicemic or it can reach the lungs which is called pneumonic.  Emperor Justinian contracted the disease but survived and the plans for uniting western and eastern portions of the Roman Empire were shattered due to reduced manpower.  The overall mortality estimated at 100 million for the two centuries the plague persisted.

The Jews were blamed for the Black Death and the first use of the maritime quarantine was in 1377 in the Venetian colony of Ragusa.  The Boards of health oversaw isolation of the sick quarantine of exposed individuals, management of medical and burial services along with record keeping.  Networks of spies were made to provide an intelligence surveillance system.  The first permanent plague hospital was opened by the Republic of Venice in 1423 on the small island of Santa Maria di Nazareth.  The initial outbreak of the modern plague was in Yunnan province of China in 1855.  By 1894, plague spread to Hong Kong killing over 2400 in two months and then it spread to India by 1896.  In a 30 year period, more than 12 million died in India, Pakistan, Bangladesh, and China.  British Indian Plague Commission proved rat’s role in transmission but assumed that rat to rat transmission occurred through rats eating their fallen comrades.  They speculated that poor sanitation was to blame so their response was draconian.  This included extreme isolation of victims and contacts, clothing and cadavers were burned, and houses were fumigated and slums razed.  In 1899, the plague reached the Hawaiian islands.  The first evidence of the disease was found in Honolulu’s Chinatown on Oahu.  The Board of Health’s solution was to burn down any buildings in Chinatown suspected of containing a source of the disease.  The original plan was to burn down only a few targeted buildings but the fire got out of control causing many of Chinatown’s homes to be destroyed with an estimated 4,000 people left homeless.  Australia suffered 12 major plague outbreaks between 1900 and 1925 originating from shipping.  Research by Australian medical officers Thompson, Armstrong and Tidswell contributed to understanding the spread of Yersinia pestis to humans by fleas from infected rats.

The plague was first introduced into the United States in 1900 by rat-infested steamships from affected areas, mostly from Asia.  Epidemics occurred in port cities.  The last urban plague epidemic in the U.S. occurred in Los Angeles from 1924 through 1925.  Plague then spread from urban rats to rural rodent species, and became entrenched in many areas of the western U.S.  Plague mostly occurs as scattered cases in rural areas.  Most human cases in the U.S. occur in two regions which are Northern New Mexico, northern Arizona, and southern Colorado, California, southern Oregon, and far western Nevada.  During plague epizootics, many rodents die, causing hungry fleas to seek other sources of blood.  People and animals that visit places where rodents have recently died from plague are at risk of being infected from flea bites.  Dogs and cats bring plague-infected fleas into the home.  Flea bite exposure results in primary bubonic plague or septicemic plague.  Humans can become infected when handling tissue or body fluids of a plague-infected animal.

Plague is now commonly found in sub-Saharan Africa and Madagascar, areas which now account for over 95% of reported cases.  Political upheaval coupled with drastic cuts in foreign assistance crippled basic government services. Millions of people were in poverty, hundreds of health clinics were closed, investments in clean water and infrastructure nose-dived, hygiene is poor.  Burial practices involve unburying the dead to consult with them when necessary.  Plague victims must be buried immediately to prevent spread of disease.  Families anticipating not being able to bury family members will decide not to bring their relatives to a hospital at all.  Options for rural population: city hospital or traditional healers, who use hand mirrors to seek advice from ancestors.  Healers have used spit to “cure” patients and claim they can fix any ailment.  In villages, people keep their cattle, chickens, and crops inside their homes to keep them from being stolen.  This attracts rats, which carry the fleas.  In the rainy season, outbreaks occur.  The rat populations decrease but flea counts increase.

The world is rapidly changing, complex and interconnected human, animal and environmental health affect on each other.  This is an ecological approach to health on collaborative, integrated, and multidisciplinary.  The effects of social and cultural changes on infectious diseases have been observed in populations.  An example would be the 2016 Anthrax outbreak in Siberia.  A heat wave led to unfreezing of a reindeer carcass that had been frozen in permafrost; carcass had spores of Bacillus anthracis.  One of the cases was a 12 year old boy who died of intestinal anthrax.  Hunter gatherers roamed over distances to find plants and find water.  Population groups were small so diseases of crowds requiring human-to-human transmission were absent.  They experienced many infections with intestinal worms, lice and fleas had adapted to humans.  They sometimes encountered microbes of wild animals and illnesses would have made isolated appearances but seldom, if ever, affected the entire group.

From 8000 BCE to 1750 CE, population of the world increased 160 times to 800 million.  Growth spurt coincided with initiation of agriculture and domestication of animals (8000 BCE).  The agricultural revolution had a big increase in agriculture and domestication of animals.  They can support denser population in which people stayed in one place and they could grow food, birth spacing shortened more children and more people required more food.  Animals frequently lived inside homes.  The agricultural revolution had some negative effects since humans and animals lived together shared the same water supply.  Squalid conditions of villages offered a paradise for rats, mice, ticks, flies, and mosquitoes.  The human diet deteriorated due to concentration on growing and eating a single crop (lack of nutrients).  The benefits of animal domestication were the hunter gatherers used food as meat and milk, clothing and fiber from wool and hides, manure for fertilizer, animal power for land transport of goods and people and for plowing.  The downside of animal domestication was the source of human disease, waste accumulated as humans settled down.  Animal bones, garbage, and feces attracted insect vectors of disease as well as wild birds and rodents carrying their own potential pathogens.

Major killers of humanity evolved from diseases of animals such as Eg, smallpox, influenza, TB, malaria, plague, measles, cholera.  These killers adapted to humans (human to human transmission) and were referred to as “crowd diseases and need dense populations in order to facilitate transmission.  Clearing of forests for planting of crops and destruction of game animals permitted the creation of new ecological niches for insects and scavenging rodents.  Ditches, irrigated fields, and pottery vessels served as breeding grounds for insects and snails.  Agricultural civilizations appeared in the riparian river environments such as the Tigris and Euphrates valley along with the Nile and Yellow Rivers where irrigation farming could be practiced.  Irrigation was beneficial for drowning weeds that would compete with crops.

The roleobalization played a big role in ancient history.  By Roman times, populations of Europe, Asia, and North Africa were joined into one giant breeding ground for microbes.  In 165-180 CE the Plague of Antonine reached Rome, killing millions of people.  In 541 CE and until 757 CE the Plague of Justinian began in Constantinople from the 6th and 8th centuries.  Researchers found tiny bits of DNA in the teeth of two German victims killed by the Justinian plague.  Malaria occurred in three countries such as Rome, England, and the Americas.  Because these diseases killed European workers on tobacco, rice, and sugar plantations, colonists imported labor in the form of African slaves who had been exposed to smallpox and malaria were less vulnerable to diseases.  Yellow fever was carried by African wild monkeys.

Reflective Questions

1.)    Over the next 7 weeks, I want to get better at making good specific details and facts in order to get better grades on my writing assignments. I’ll start getting more help by going to the writing center and even from Col Ticen because right now it seems like I still can’t write all that well on my own.  Whenever I get a writing assignment I will try to think it through and if I want help on something I can’t do I will get help right away. I feel that writing is one of the hardest classes for anyone especially us rats since were busy with cadre training and athletics. The main thing I need to work on is time management with writing essays and trying to not doze off in class.

2.)    Over the next 7 weeks, I want to help my peers become better writers by helping them try to come up with better details, facts and ideas because that seems to be everyone’s main issue with writing. The one thing I want to help them with is to cite things correctly in order to avoid plagiarism and stay awake in class.