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1.2: History of Epidemiology

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    92510
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    Learning Objectives

    By the end of this chapter, the learner will be able to

    • Learn about the history of epidemiology, which parallels the history of public health
    • Examine the history of epidemiology as a relatively new science
    • Illustrate the history of epidemiology with events that not only happened in the traditionally European tradition, but also in the United States, and the Americas.
    • Create a history of the field of epidemiology and public health in the United States.

    Epidemiology: Classic historic events

    The following content intends to provide only the most basic historical events in epidemiology. It does not intend to be exhaustive, but at least it will cover the most salient events that influenced the development of what it is known now as the field/science of epidemiology. From ancient civilizations, the time of the Greeks and Romans, and the 17th, 1800s, and 1990s to the 20th and 21st century the main purpose of epidemiology and public health has been the search for determinants that can explain causation and disease, the discovery of treatments and moreover, the prevention and control of disease, and related health problems

    Medicine/Public health in the time of the Greeks

    Although epidemiology is considered a new science, even before it was recognized as a science, it probably started in the times of the Greeks, who attributed disease causality to environmental factors influenced by the gods, the presence of epidemics, and the deadly toll of diseases were influenced by those factors. Also, at the time of the ancient Greeks, the disease was also explained by what is known as, the theory of the four ‘fluids’ (blood, phlegm, yellow bile, and black bile) that is, in turn, premised on the theory of the four elements (fire, earth, water, and air) and their four corresponding qualities (heat, dry, humid and cold).[1]

    4_body_fluids-300x300.png
    Image of ‘the concepts of the four fluids/four elements’. Public Domain. Wikipedia.

    Early sanitation efforts, water systems and toilets
    Then, the Romans, who developed aqueducts and sewage systems to prevent the development of diseases related to the lack of proper sanitation; brought water to their cities improved sanitation, and personal hygiene, which are essential for good health. [2]

    Pont_du_Gard_BLS-scaled-1.jpeg
    ‘Pont du Gard’, By Benh LIEU SONG , CC BY-SA 3.0, Wikimedia.

    It is the Romans who also developed the first rudimentary system of disposition of excretas (or, excreta) before what we know as toilets were invented.[3]

    Ostia-Toilets.jpeg
    ‘Ostia Toilets’(Ancient Roman latrines / latrinae), Public Domain,Wikimedia commons.

    Medieval period: The Black Death (or, Plague)
    Then, the medieval period with the presence of deadly diseases such as the plague. [4]

    Doutielt3-Plague-300x181.jpg
    ‘Citizens of Tournai bury plague victims,’ by Pierart dou Tielt, Wikimedia commons, Public Domain.

    The Renaissance

    With the advent of the sciences and arts during the Renaissance period, the initial work on medicine, and anatomic studies started. Several individuals flourished during those times, bringing new ideas, and discoveries including Girolamo Fracastoro (1478–1553), an Italian physician who introduced the term ‘fomites‘ still in use today in Epidemiology to refer to those inanimate objects that might contribute indirectly to the transmission of an infectious disease. And of course, the anatomical draws and notes done by Leonardo DaVinci were part of the contributions from this era. [5]

    davinci-150x150-1.jpeg
    Image of ‘The Renaissance man’ by Leornardo DaVinci. Public Domain.

    Medicine without microscope

    If the history of medicine and epidemiology goes back to the beginning, there is a common factor for many events (that make history), they revolved around the search for causation, and how to prevent and treat disease. Since most deaths in earlier times of the humanity were caused mostly by infectious agents (usually bacteria), the progress in identifying these causes had to wait until the discovery of the microscope since most of these agents could not be seen with the naked eye.[6]

    File:Old-microscopes.jpg
    ‘Old-microscopes’. Image by Idal. Wikimedia Commons. Licensed CC BY-SA 3.0 Unported

    In this context, the first systematic methods used to identify causation are attributed to the father of medicine, Hippocrates who in about 400 years of the contemporary era was able to propose that there is a connection among three major elements of nature and health or disease, these are: air, water, and place (as we will see later in the book, place is usually referred as location – where people reside/live); he proposed for example that in some cases the ‘bad air’ can cause disease, or, the ‘quality of the waters’ as he called, and the place in which people live such as high altitudes and other geographical characteristics, especially the soil, and terrain.[7]

    File:Hippocrates bust and title page Wellcome L0041093.jpg
    ‘Hippocrates bust and title page’, image from Wikimedia Commons. Licensed CC BY 4.0 International.

    Another important person in the history of epidemiology is, John Graunt, a London cloth merchant who lived in the middle of the 17th century. Due to his work, he is considered the first demographer and initiator of the concept of vital statistics.John Graunt In 1603 in London, Graunt compiled the first register of births and deaths in England, under the name of, the ‘Bills of Mortality’. This is considered, the first systematic recording of deaths known in the history of record keeping and reporting of deaths, and other vital events. Graunt’s intentions were to show that human life conforms certain predictable statistical patterns, he wrote for example that deaths varied by age, sex, who died, of what, and where they died (the location), and when (the time of death). [8],[9]

    John Graunt - Scientist of the Day - Linda Hall Library JohnGraunt-206x300.png
    ‘The Bills of Mortality’, Image from Linda Hall Library. Public Domain. John Graunt, Image from Wikimedia Commons. Public Domain.

    In the other in which events are presented here, the next person who made significant contributions to epidemiology and public health is Dr. John Snow – already discussed in another section of the chapter. One of the main remarks is that Dr. John Snow is considered the father of public health.

    File:John Snow.jpg
    Dr. John Snow. Image from Wikimedia Commons. Public Domain.

    Dr. John Snow (1813-1858) was a respected physician, and the anesthesiologist to Queen Victoria of England, he studied cholera throughout his medical career, and from his studies, he established sound and useful epidemiological methodologies. He used several research methods that were highly advanced for this time, but also methods that are still valid today. Using a ‘natural experiment’ approach Dr. Snow studied an epidemic of cholera that developed in 1849 in London (already discussed previously in this chapter).

    Snow-cholera-map.jpg
    Dr. Snow’s map, image from Wikimedia Commons. Public Domain.

    He developed a famous map, that at that time was considered ‘scandalous’ because it was not drawn to scale but it provided an operational system in which he was able to identify and register where persons with cholera lived and worked, the distribution of cases was mapped using a dot map (this is considered an incipient beginning of the geographic information systems GIS map known as a choropleth map ), the collected information was used by him eventually identified that the cause of the cholera epidemic was a problem with contaminated drinking water from one of the main source of water in London. Through his interventions, Dr. Snow was able to stop the cholera epidemic.[10],[11]. Cholera in the United States During the winter of 1848-49, an outbreak of cholera was reported in New Orleans, Louisiana. A disease that had killed thousands of people in Europe had also affected the U.S. population in the South. This came after a brief epidemic of cholera in 1832. According to an article published in the famous local newspaper, The Times-Picayune, the source of the outbreak came from the contagion of locals with the arrival of a passenger ship that was bringing immigrants from Liverpool and Le Havre on December 22, 1948. In a period of two months, the outbreak took the lives of approximately 3,000 New Orleans residents who were not prepared to deal with the contagion. The local newspaper did not realize that the cause of the disease was already known as an illness caused by contaminated water with the Vibrio Cholera bacterium; however, some locals had noted that most people affected by the outbreak were low-income individuals who lived in improper sanitary conditions, and who may have no access to clean drinking water. The cholera outbreak mentioned above has several similarities with the epidemic described by Dr. John Snow in England in 1849, people affected were those with low access to health education, and proper sanitation. The affected residents were reported as people of “irregular habits.” In the same article, some numbers also reported that some of the victims of cholera were also people from Ireland, Germany, England, Spain, Prussia, France, and Switzerland.[12]

    The Duke of Orléans visiting the sick at the Hôtel-Dieu hospital, during the cholera outbreak, in 1832. Painting by Alfred Johannot, 1832.
    ‘The Duke of Orléans visiting the sick at the Hôtel-Dieu hospital, during the cholera outbreak, in 1832.’ Painting by Alfred Johannot, 1832. Licensed as Public Domain, from Musée Carnavalet.

    A response to the Cholera epidemic: The creation of a school of public health in New Orleans

    When I was a student in the School of Public Health at Tulane University, New Orleans, Louisiana, I heard so many times from professors that problems such as the cholera epidemic in 1832 were one of the reasons for creating one of the first public health schools in the U.S., the Tulane School of Public Health and Tropical Medicine founded in 1834; other similar public health problems were also part of the reasons, also as part of its origins. These other health issues malaria, yellow fever, and smallpox; all affected the region, and a group of physicians founded a medical college in New Orleans (not yet known as the School of Public Health) so training on these issues and because of the great need to education of tropical medicine problems in Louisiana and other parts of the South.[13]. See below an old (historical) picture of New Orleans:

    The City of New Orleans, and the Mississippi River, Lake Pontchartrain in Distance, 1885. (Library of Congress).
    “The City of New Orleans and the Mississippi River c1885” Licensed Public Domain, Library of Congress.

    The discoveries of Dr. Robert Koch and its importance in public health

    It is probably insufficient to have a section on historical events, or, individuals and their works without mentioning Dr. Robert Koch (1843-1910), a German physician and one of the main founders of bacteriology as a science, among other great accomplishments he discovered the anthrax disease cycle and the bacteria responsible for tuberculosis and cholera. He received the Nobel Prize for Physiology or Medicine in 1905 for his research on tuberculosis.

    RobertKoch cropped.jpg
    Dr. Robert Koch, image from Wikimedia Commons. Public Domain.

    Dr. Koch’s work has been pivotal for the work on causation since most of the infectious diseases in his time were bacteria, or bacilli. He developed what is called, the Koch postulates that include the following four criteria: (1) The microorganism must be found in diseased but not healthy individuals; (2) The microorganism must be cultured from the diseased individual; (3) Inoculation of a healthy individual with the cultured microorganism must recapitulate the disease; and finally (4) The microorganism must be re-isolated from the inoculated, diseased individual and matched to the original microorganism. These postulates are the founding for the reproducibility of experimentation with infectious agents, and the search for health determinants.[14]. Connecting the information above How is Dr. Koch connected to the history of the cholera epidemic mentioned above? The answer is that if Dr. Snow had access to a microscope and had the bacteriological knowledge that was available in the times of Dr. Koch, including his own experiments with bacteria, then, Dr. Snow would not say that the contaminated water (in the time of his assessment of the cholera epidemic in London, 1849) contained a great amount of “impurity in the form of small white, flocculent particles…[visible to the naked eye]”. [15] but to the presence of the Vibrio cholerae bacterium. So, although separated by decades of difference, a connection exists between Dr. Snow’s studies and Dr. Koch’s discoveries of the presence of bacilli in contaminated water.[16]

    The foundations of the concept of vital statistics in public health

    Another individual who made a difference in the field of epidemiology is, William Farr, a British epidemiologist who was appointed compiler of abstracts in England, in 1839. His work examined the linkage between mortality rates and population density, it also created the foundation for the concept of vital statistics. Farr’s contributions provided the foundation for the classification of diseases (ICD system).[17]

    1280px-PSM_V23_D302_William_Farr.jpg
    ‘William Far’, image from Wikimedia Commons. Public Domain.

    Systematization of the science of epidemiology

    And, coming back to home the United States, and according to most historians in the field of epidemiology and public health, the first epidemiologist in the United States was Dr. Wade Hampton Frost, who in 1921 was appointed professor of epidemiology at Johns Hopkins University School of Hygiene & Public Health, Baltimore, Maryland.

    Wade Hampton Frost.png
    Dr. Wade Hampton Frost, image from Wikimedia Commons. Public Domain.

    Based on what it has been presented above, this means the beginning of the teaching of epidemiology in a public health school in the U.S., he advocated for the use of quantitative methods to support public health research that at that time was mainly research on the study of infectious diseases. [18] Another individual who made great contributions to epidemiology and public health in the United States, Dr. Alexander Langmuir is another great scientist who established the CDC’s Epidemiological Intelligence Service (EIS).

    Alexander Langmuir.jpg
    Dr. Alexander Langmuir, image from Wikimedia Commons. Public Domain.

    Dr. Langmuir made an extraordinary contribution to not only the CDC as an institution, but also to public health in general. From 1949, he served as the first Chief Epidemiologist at CDC and remained in that position until 1970. Prior to this, in 1952, he convened the first Conference of State and Territorial Epidemiologists, which became the organization representing epidemiologists in the United States. Overall, Dr. Langmuir defined disease surveillance at CDC.[19] Note: All the above individuals made great contributions to the field of epidemiology and public health. The names of more individuals could continue, but the focus of the chapter at this point will continue with the establishing of a parallel between the main influence of public health and epidemiology which is the British system. It is important to recall that the first school of public health in the world was the London School of Hygiene and Public Health, which for a long time, was the only school in the world, hence its main influence in the United States public health system.

    The history of epidemiology in the U.S. and England

    What I am proposing here is that in the U.S., we start writing about our own history of public health and epidemiology, not because the historical events of Europe (especially in England) don’t matter (because they do, they are important milestones in the history of public health in general, and epidemiology); but because there is need to have historical information that applies to our times and needs of the population we served in public health.

    The Parallel of the history of public health in England and the United States:

    “The Shattuck Report” in the U.S. and the progress of public health in England

    The history of public health in the United States also saw an event that marked the beginnings of what is essentially the beginning of public health in the U.S. This event is the publication of the Shattuck Report, written by Dr. Lemuel Shattuck and published in 1850 by the Massachusetts Sanitary Commission, it reports on the serious health problems experienced by certain groups of people, who were also living in unsanitary conditions in the city of Boston. Among the recommendations given to solve these problems, the report recommended the creation of a state health department and local boards of health in each town so public health interventions to address the issues were developed and implemented. [20],[21]

    Shattuck-report.jpg
    The Sanitary Commission of Massachusetts 1850, image from the Welcome Collection, Public Domain

    As a result (of the Shattuck’s report) in 1866 in New York City for the first time in the United States an organization as the report recommended was created. This is considered by many as the beginning of public health in the U.S. A picture of Dr. Shattuck is shown below:

    Lemuel-Shattuck1489.jpg
    Dr. Shattuck, image from London School of Hyg, & Trop. Med.

    These early beginnings of public health in the U.S. contrasted so much with the reality of public health in England and France which were more concerned with how to properly administer and manage the incipient healthcare system already in place. In other words, the U.S. at that time (1850) was dealing with issues that were a thing of the past in England, or at least something that they had under control already.[22] Again, this summary of the impact of the Shattuck’s report is another example that this country could learn from the public health lessons that England had already experienced. Parallel Dr. John Snow and Cholera (in England) and Seat belts’ use in the U.S.
    For example, Dr. John Snow (1884) in England, used epidemiological methods to identify the cause (origin) of the cholera epidemic that was killing thousands; and developed a strategy to stop the epidemic, which was basically removing the pump’s handle of the contaminated water source; in this manner, people would stop drinking the contaminated water, and the epidemic stopped.[23] See the image of the pump below:

    John-Snow-Pump-300x200.jpg
    “John Snow pump and pub” by mrlerone is licensed under CC BY-NC-ND 2.0

    Seat belts lawin the U.S.
    A similar example can be found in the U.S. when the use of seat belts started as a public health measure to save lives during motor vehicle accidents, in the early 1970s when the measures were implemented, most people did not buckle up; they thought it was optional; but with the pass of time, people started seeing the benefits of seat belt use.[24] When the regulations are enforced, people who drive without a seat belt will get a traffic ticket from the police; and just because getting tickets is not pleasant, but also, just by knowing that the ticket is recompense for not wearing a seat belt, has made the measure very effective. It was probably the best way to make people use (consistently) seat belts while driving; and nowadays, it has become a habit, a norm. [25].

    Seat Belts Have Saved an Estimated 255,000 Lives Since 1975
    Bar graph showing the cumulative lives saved by seat belts. The graph shows a plateau from 1975-1997, then a steady increase from 1997-2008.

    Image from CDC. Public Domain.

    Lesson learned: During Dr. Snow’s time in England (1884) the epidemic stopped when he removed the water pump handle that delivered the contaminated water. In this manner, people stopped drinking from a contaminated water source. Similarly in the United States, when the use of car seat belts stopped the growing number of motor vehicle accidents when the seat belt law took place in the year 1968. People need to change behavior, but without removing barriers is hard for people to change. Laws help to enforce public health policies.

    Another parallel between England and the United States is the second wave of immigrants in the U.S.

    Most books in epidemiology used the historical events of public health in England in order to draw a parallel with the U.S. history of public health; and this works well until we realize that the history of public health, and epidemiology in the U.S. has to do with one major issue, the wave of immigrants from distant countries, and how these immigrants dealt with the current sanitary conditions, housing, and environment conditions of their time, especially those immigrants who decided to reside in New York; which was not prepared to receive such high numbers of people, especially the unsanitary conditions of the buildings that many of these immigrants were allocated in the city. Crowdedness, lack of proper disposal of excreta, and high levels of cross-contamination of food, and water were typically in an Irish immigrant household (say, apartment) in New York. These immigrants faced a challenging time keeping themselves healthy and alive (especially their children, who in many cases died of dysentery, or any other type of oral-fecal-related disease. [26]

    tenement.jpg
    “New York, NY, yard of tenement (between 1900 and 1910)” Image from
    Library of Congress. Public Domain.

    These above-mentioned conditions made the epidemiological landscape very much different from those people living in Europe (just say, in England) where more epidemiological research was conducted at that time and more advances in public health have been implemented. So, the U.S. epidemiology in this case was a little different – probably many methodological similarities, or, very different in the sense that the U.S. was experiencing a sanitary public health crisis while Europe was already ahead of the U.S. around sanitary controls, and housing conditions, to mention some of the public health issues at that time.[27]

    Remarks

    In this book, the history of public health in England is used to correlate with the U.S. public health (and epidemiological) history, which had several similarities, but at the same time, different because what affected the population in the U.S. was a thing of the past in Europe. Most events used to write the history of epidemiology in Europe occurred later in this new world that we know now as the Americas, which includes the United States.[28]

    Next parallel: Tobacco use and cardiovascular disease as a public health problem in England and the United States Another historical event (or, series of events) in the history of epidemiology and public health in England versus the United States is the problem of tobacco use and its effects on health, specifically in the connection between tobacco use and heart disease.

    The early regulations started earlier in England, and the English people started hearing about the noxious effects of tobacco use (mainly smoking cigarettes) way before people in the U.S., and it was not until 1957 when this country (the U.S.) became aware of the need to study (do some research) the problem, and considered for the first time to start regulations on its use. In this regard, one of the main public health event on the noxious effects of tobacco is the released of the U.S. Surgeon General’s Advisory Committee on Smoking and Health report (on January 11, 1964), which concluded that cigarette smoking is a cause of lung cancer and laryngeal cancer in men, a probable cause of lung cancer in women, and the most important cause of chronic bronchitis.[29].

    Although now, it seems something not of such major importance, it represented a big step in the search for health determinants at that time. Medicine also benefited from these studies, because now, physicians and other health care providers have data from their own people about the effects of chronic tobacco use and cardiovascular disease.

    Luther L. Terry, M.D., Surgeon General of the U.S. Public Health Service, 1964 Picture of the 1964 U.S. Surgeon’s General Luther L. Terry, M.D., who released the first report on the nocebo effects of smoking on health. By CDC. Public domain.
     

    Another historical public health/epidemiology event in the United States: Research on Cardiovascular Disease
    In the search for the risk factors associated with Cardiovascular disease three major cohort studies have been conducted, these are, The Framingham Heart Study in Massachusetts, The Bogalusa Heart Study in Louisiana, and the San Antonio Heart Study in Texas. Each one of these studies will be briefly described in the following paragraphs, and more detailed information will be also provided in the chapter on study designs, and section on cohort studies.[30] The Framingham Heart Study
    It represents one of the greater milestones in the epidemiology of cardiovascular disease studies in the U.S., and it also became well-known later in the world. The Framingham Heart Study (FHS) in Massachusetts, took its name from a town in eastern Massachusetts, U.S. which was selected as the site of the study. [31] See a picture of the Framingham City Hall below:

    image
    “Town hall in Framingham, Mass.” Encyclopedia Britannica. EagleOne GNU Free Documentation License Version 1.2

    The Framingham Heart Study is the first cohort to study the U.S. population on the issue of heart disease, and its related risk factors. It started in 1948 with a small group of individuals, and it is still collecting information about the white population in the U.S., and heart disease behavioral lifestyle risk factors. The findings of the Framingham Heart Study provided much of the common knowledge that people now have about heart disease, including the effects of exercise, diet, and smoking on cardiovascular disease.[32]

    The Bogalusa Heart Study

    Later in the history of epidemiology in the U.S., there was another major study focused on cardiovascular disease; but this time on the black population, its name the Bogalusa Heart Study, Bogalusa is a city (mainly black population) in Washington Parish, Louisiana, United States. It is the principal city of the Bogalusa Micropolitan Statistical Area, which includes all of Washington Parish and is also part of the larger New Orleans–Metairie–Hammond combined statistical area. [33]
    See Louisiana Map below:

    Bogalusa-map-300x207.jpg

    Bogalusa became well-known because of this study, which began in 1972 being the main investigator, Dr. Gerald S. Berenson, a Bogalusa native and pediatric cardiologist who recognized the need for investigations into the childhood antecedents of adult cardiovascular diseases.[34] I had the privilege to meet Dr. Berenson while doing my public health doctoral studies at Tulane University in New Orleans. [35]. To see additional images of the city of Bogalusa, see below:

    Bogalusa_City_Hall.jpg “Bogalusa City Hall“. Wikimedia Commons. Licensed CC BY-SA 4.0

    The main contributions of the Bogalusa Heart Study among others include the following: adult heart disease, atherosclerosis, coronary heart disease, and essential hypertension begin in childhood. Cardiovascular risk factors can be identified in early life, but the levels of risk factors in childhood are different than those in the adult years. In addition, another great contribution of the Bogalusa Heart Study among others is that it is targeted (collected data) to African American children (while the Framingham targeted mainly adults). [36]

    The next step, the San Antonio Heart Study (SAHS)
    With the past of time, the need to have information (data) about cardiovascular disease among another major ethnic group in the U.S. became one of the major reasons to conduct another famous cohort study on the Latino/Hispanic population in the U.S. The name of the study, is San Antonio Heart Study, San Antonio, Texas. See a picture of San Antonio below:

    File:Downtown San Antonio.jpg “Downtown San Antonio.” Wikimedia Commons. CC BY-SA 3.0

    The San Antonio Heart study is an ongoing study that focuses not only on cardiovascular disease but also on the study of type II diabetes in Latinos residing in the U.S. The author could not find a specific website for the San Antonio Heart Study, but the following is a journal article that provides substantial information about it. [37]

    My personal critique/comments of the San Antonio Heart study is that it lacks representativity of the different U.S. Latino ethnic groups, by being mainly focused on Mexican-American, which constitute a great majority of the population of Latinos in the U.S. and excluding the great numbers of new Latino immigrants from other countries, and regions especially Central America and the Caribbean, the data results cannot be generalized to the rest of the U.S. Latino population in the U.S., but on the positive side, the contribution of the San Antonio Heart Study (SAHS) cannot be denied because it represents pioneering research on two major problems (cardiovascular disease and type II diabetes) of morbidity, and mortality among the U.S. Latino population.

    Key Takeaways

    As we had presented above, the study of cardiovascular disease, and its associated factors represent one of the major milestones in epidemiological investigation in the U.S. and a history of the field of epidemiology without looking at these studies will be short; and that is probably one of main reasons for including them in this historical section of the book.

    In addition to those parallels covered above, one more issue I want to review is the issue of research in the field of epidemiology in the U.S. and public health. As has been seen in the examples above, the major research efforts on the topic of cardiovascular disease in the U.S. has reflected the systemic problem of race, why some ethnic groups have been excluded from some studies? Why have certain ethnic groups been subjected to deception and mistreatment in certain research studies? In the name of sciences and medical advances, abuses have been made. The following is an example of this type of problem.

    Medical and Public Health Research going wrong in the U.S., the case of the Tuskegee syphilis study

    The Tuskegee syphilis study (called at that time, the ‘Tuskegee Study of Untreated Syphilis in the Negro Male.’) took place in Macon County, Alabama during the years 1932 and 1972. This time study of the natural history of syphilis was conducted among the African-American population in the area. Without a person’s informed consent, the clients in the study were left without treatment for syphilis and were offered regular medical care for other health problems but not for syphilis. They were also offered free meals and burial insurance. [38]

    image
    Image from CDC Public Health Image Library (PHIL).

    According to the CDC, this photograph was taken around 1932, it shows participants in the Tuskegee Syphilis Study. In this picture, an African-American man was being X-rayed, while in the standing position.

    At the beginning of the study, the number of participants included 600 African-American men, from this group, 399 had syphilis and 201 did not have the disease. During the time of the study, the investigators told these men that were being treated by “bad blood,” a common term at that time that was used to describe some common diseases such as syphilis, anemia, and fatigue. The study lasted for 40 years, although the men participating in the study, were told that the study would last 6 months.[39]

    The Tuskegee syphilis study is an example of human experimentation on the clinical history of a common infectious disease which by that time had treatment already available. The withholding of the treatment exposed the study participants, their families, and generations of African Americans in the South to syphilis. For this reason, this study is frequently cited as an example of what an investigator is not supposed to do in conducting research, especially research on human subjects. The question that usually comes to mind when the author reads about this study is, what can be done to prevent similar situations in the future of research in the U.S.? And the question remains open.

    The epidemic of smallpox in Europe and then, later in the United States

    From the list of plagues that affected the world population in the past, one of the major problems is smallpox, a disease now eradicated. A disease caused by the Variola virus . It caused millions of deaths especially during the Medieval times, although it is believed to have existed for at least 3000 years. [40]

    Smallpox_virus_virions_TEM_PHIL_1849-scaled-1.jpeg
    “Variola virus” image from CDC/ Dr. Fred Murphy; Sylvia Whitfield, Public domain, via Wikimedia Commons

    The person who created the first smallpox vaccine was Dr. Edward Jenner, an English doctor who as part of his observations noted that milkmaids who had gotten cowpox were protected from smallpox, which means that they received immunity (this concept was unknown at his time) from having the disease, this became the base for the development of the smallpox vaccine. Having a vaccine made a tremendous difference in the history of the disease, which basically contributed to its eradication. [41], [42]

    An external file that holds a picture, illustration, etc. Object name is bumc0018-0021-f01.jpg
    “Edward Jenner (1749–1823), Public Domain, from the National Library of Medicine

    Smallpox in the United States – a terrible experience for Native Americans
    Smallpox was mainly a European problem for a long time, until the colonization of the new world (America) in which the colonizers brought the disease to the natives, which did not have immunity since they were never exposed to the smallpox agent. So, smallpox killed thousands of natives (not only in what is known as North America today but also in the Caribbean and South America. One of the worst examples is the killing of Native Americans in the United States when the colonizer gave (as a gift, at least once) blankets intentionally contaminated with smallpox – this is also an example of an early episode of terrorism using biological weapons, as it was expected the strategy worked, and again entire populations of Native Americans were killed by the disease. [43]

    File:Treaty of Penn with Indians by Benjamin West.jpg
    “Treaty of Penn with Indians by Benjamin West”, Public Domain Wikimedia Commons.

    Influenza Pandemics in History

    The history of epidemiology and public health has been shaped by the presence of pandemics: plague, flu, and recently, coronavirus or, COVID-19. Throughout history, these pandemics have been responsible for the death of thousands of people around the world. Overall, what has changed from ancient times to today’s public health is the availability of vaccines, and the improvement in water and sanitation around the world, with major gains for developed nations who have better systems of drinking water, and sanitation. Until recently, the fear of a major pandemic has been for a worldwide-scale flu that could kill thousands of people. But instead of the flu, the world received the coronavirus pandemic, which is still around. Since flu has been the major fear before the coronavirus, this section will cover some of the major events of flu pandemics.

    Flu pandemics

    In general, flu pandemics have been repeated in history every 100 years, and because of that the ‘expected’ and ‘predicted’ pandemic was on flu (and not coronavirus).[44]. Because of its importance in history, the first major pandemic that appears usually in most history books is the flu pandemic.

    The flu pandemic of 1918

    The 1918 Influenza (flu) Pandemic (also called, the Spanish flu, because of the great mortality in that country at that time). This famous pandemic lasted from 1918-1919 and killed 50 to 100 million persons worldwide. The pandemic had three waves as it is represented in the following image:

    Íomhá:1918 spanish flu waves.gif

    “1918 spanish flu waves,” Image Licensed Public Domain, Wikipedia.

    As is seen in the graph/image above, the second wave of the 1918 flu pandemic was higher/stronger than the first, and the third wave was also higher than the initial wave. For this reason, the 1918 flu pandemic was called, “The Mother of All Pandemics,”[45] Of course this designation has been before the current coronavirus pandemic. There was also a 1927 flu pandemic that was less noticed around the world, but it killed a significant number of people, especially army soldiers in the United States.[46]

    The 2009 H1N1 influenza pandemic: a repeat of the 1919 pandemic
    The specific time of this pandemic is from 2009-2010. The disease was first identified in the United States and eventually was named the 2009 H1N1 influenza. The first two cases of the disease were reported by the Centers for Disease Control and Prevention (CDC) in April 2009, after this, the number of cases grew to 60 million by summer 2010. The pandemic also attacked several other countries in the world, and it was known to prefer the group of people 14-64 years, with those aged 65 and older as the less affected group.[47], [48] This pandemic should have served as a lesson for the U.S., but a lot of skepticism grew that the possible for another major pandemic was not possible, or, if this would happen then, the country had enough public health resources including vaccines to control the problem, which has been proven wrong with the current coronavirus pandemic making manifest that the U.S. public health system was not prepared for a pandemic.

    Helen Vaccine Graph
    “Comprehensive vaccine initiative report,” Image by, from CIDRAP Comprehensive Influenza Vaccine Initiative report [49], [50]

    The most recent pandemic: the COVID-19 pandemic due to Coronavirus 2019-current

    The prediction of a new pandemic was always there but the medical and public health preparations were never in place, so, the pandemic started in Wuhan, China with several infected persons never seen before, the agent coronavirus named COVID-19 because of the year in which it was reported as the cause of the pandemic. The news was everywhere, but the United States did not pay attention to the situation, until almost two months later in March 2020; acknowledging and responding to the pandemic was proven bad, because the country and the world did not have a vaccine for it, nor the U.S. had the public health infrastructure to respond properly, there was a lot of unknown about the disease, and especially its form of transmission; the measures taken since the beginning did not have a social acceptance in a society that values so much its personal freedom, and having the federal government, and public health authorities, and experts tell the public to wear a mask, stay at home and related mandates created an epidemic of misinformation, and contradictory messages that have been hard to eliminate until today.[51],[52]. I have found an image -shown below that summarizes some of the reasons for this campaign of misinformation that has been one of the major problems of the COVID-19 pandemic.

    image
    “Fast-Slow-Science,” By Dasaptaerwin, Licensed CC 4.0 International, Wikimedia Commons.
    There is also an article that refers to more details about the content of the image.[53]

    The agent, and the statistics As mentioned before the agent of the coronavirus has many different variants, including those variants that cause the respiratory illness, called COVID-19 or, SARS-CoV-2 that may have originated in an animal (still not clear which type), and the virus mutated causing the illness in humans.[54]

    Novel Coronavirus SARS-CoV-2&ndash;This scanning electron microscope image shows SARS-CoV-2&mdash;also known as 2019-nCoV…
    “Novel Coronavirus SARS-CoV-2 (or, COVID-19) electronic microscope image,” Licensed Public Domain,, from rawpixel.

    The number of infected people has been high since the beginning of the pandemic with excess mortality, which has been the main feature because before an infected individual died, the need for hospitalizations had been never seen in decades, and probably in the last century. The COVID-19 pandemic has officially affected 191 countries and territories in the world. Most of the data collected ranges from 2020-2021.[55] Recent estimates and reports are still only available on websites such as one of the most popular, which is the Johns Hopkins Coronavirus Resource Center. [56]. Since the estimates are still changing, I decided to present a map of the world’s distribution of the pandemic to illustrate the content.

    image
    “Global distribution of estimated excess mortality rate due to the COVID-19 pandemic, for the cumulative period 2020–21” Image from an article by Haidong Wang, H., Paulson, KR., Pease, SA., Watson, S. et al.[57]

    At the time I completed this chapter, more and more information about the COVID-19 pandemic became available on the World Wide Web, scientific medical journals, and grey literature, especially from popular magazines, or open educational resources. For now, the information above has been written with the intention of having an idea of the history of public health and epidemiology throughout two to three centuries.

    Summary

    Although a historical review of events, and individuals, it shows that the history of public health and epidemiology are intertwined. The historical events mentioned in this chapter confirm that epidemiology as a science has made great contributions to medicine and public health, in the search for determinants and the design of effective public health interventions.


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    This page titled 1.2: History of Epidemiology is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by H. Giovanni Antunez via source content that was edited to the style and standards of the LibreTexts platform.