History of Public Health: Milestones & Figures

1. King Saud UniversityCollege of Business AdministrationDepartment of Health Administration Masters` Program PA 507 –Introduction to Public Health First Semester 1440/ 1441 Mohammed S. Alnaif, Ph D.alnaif@ksu.edu.sa Dr. Mohammed Alnaif

2. History of Public Health Learning Objectives Describe major historical milestones in the development of public health and identify major figures such as John Graunt, John Snow, and Lemuel Shattuck. Compare and contrast endemic, epidemic, and pandemic diseases. Describe the origins and content of public health responses over history Broadly characterize the contributions and value of public health. Dr. Mohammed Alnaif

3. History of Public Health SOME TERMS YOU SHOULD KNOW An epidemicrefers to the outbreak of a disease in a localized group of people. It can be infectious and spread from person to another by: Carrier, people who are susceptible to the disease, although they may not be affected by it themselves. Vector, intermediate organisms that carry the disease but do not have it, such as the anopheles mosquito for malaria or fleas for the plague. Dr. Mohammed Alnaif

4. History of Public Health SOME OTHER TERMS YOU SHOULD KNOW An epidemiccan also be caused by the sudden introduction of some pathogen. Epidemicsare usually limited in time, although the time can be long as we are seeing in the case of AIDS. Dr. Mohammed Alnaif

5. History of Public Health SOME OTHER TERMS YOU SHOULD KNOW The definition of endemic refers to a disease or something that is native to or commonly found within an area. An endemicdisease is said to be present if cases are continually occurring in some region, for example the presence of river blindness or malaria in certain parts of Africa. Dr. Mohammed Alnaif

6. History of Public Health SOME OTHER TERMS YOU SHOULD KNOW A pandemic is the worldwide spread of a new disease. When an epidemic escapes its local region and starts to affect people over a large portion of country or even the world, it said to be pandemic. In this regard, the bubonic plague of the fourteenth century would more properly be called a pandemicrather than an epidemic Dr. Mohammed Alnaif

7. History of Public Health History of Public Health For many centuries, disease was synonymous with epidemic. Infectious Diseases, including horrific epidemics of infectious diseases such as the Black Death (bubonic Plague), leprosy, and cholera, were phenomena to be accepted. Science had not determined that specific micro-organisms were the causes of epidemic, avoidance had long been the primary tactic used. Dr. Mohammed Alnaif

8. History of Public Health History of Public Health Avoidance meant evacuating the general location of the epidemic until it subsided or isolating diseased individuals or those recently exposed to diseases on the bases of mix of fear, tradition, and scientific speculation. The work of public health pioneers such as EdwardJenner, John Snow, and Edwin Chadwick illustrates the value of public health, even when its methods are applied amidst scientific uncertainty. Dr. Mohammed Alnaif

9. History of Public Health History of Public Health For thousands of years, populations have been concerned with sanitation, housing, the provision of safe, clean food and water, and the control and treatment of disease. Public health evolved to address these concerns. These issues continue to be important today, along with the many new topics constantly added to the field. Dr. Mohammed Alnaif

10. History of Public Health History of Public Health Although it was not always identified as a separate discipline, we can see examples of publichealth concerns in the earliest civilizations. The great writers, philosophers, and physicians of ancient Greece tell us of the beginnings of publichealth. Dr. Mohammed Alnaif

11. History of Public Health History of Public Health In “Airs, Waters and Places,” Hippocrates, the esteemed Greek physician, discussed the relationship between one’s environment and health. He considered climate, soil, water, nutrition, and lifestyle to be important predictors of health outcomes. In addition, Hippocrates, distinguished between endemic and epidemic diseases. Dr. Mohammed Alnaif

12. History of Public Health History of Public Health The Romans continued the medical inquiries of the Greeks and formalized public health administration systems. The Romans constructed vast water supply and sanitation systems and established government positions dedicated to overseeing these systems. They also created offices to oversee the food supply at markets and to assess the public bathhouses. Dr. Mohammed Alnaif

13. History of Public Health History of Public Health The Middle Ages were marked by to major epidemics of bubonic plague: the Plagueof Justinian in 543 and the Black Death in 1348. The etiology, or cause, of bubonic plague was not understood during the Middle Ages, but poor living conditions were known to contribute to frequent epidemics. Today, we know bubonic plague is caused by infection with Yersinia pestis, a bacterium transmitted from rats to humans by the fleas that bite both. Dr. Mohammed Alnaif

14. History of Public Health History of Public Health In the Middle Ages, overcrowded cities with unreliable municipal sanitation systems and close proximity of animals and humans allowed rat populations to flourish and bubonic plague to spread rapidly. Near the end of the Middle Ages, around 1200, European cities began passing laws to improve public health and combat epidemics. These measures included the establishment of slaughterhouses and the regulation of livestock possession. Dr. Mohammed Alnaif

15. History of Public Health History of Public Health The long - standing practice of isolating people with leprosy was extended to those with the bubonicplagueduring the Middle Ages. Isolationis the separation from healthy individuals those people who are actively ill or who exhibit symptoms of illness. At the same time, in Venice ships entering the port were segregated to prevent the introduction of new diseases. This practice led to the term quarantine, which is the separation of people who are not ill or symptomatic but who have been exposed to an illness. Dr. Mohammed Alnaif

16. History of Public Health History of Public Health The Renaissance (late 1300s to early 1600s) brought great strides in scientific discovery, laying the groundwork for advances in public health. During the Renaissance, two theories on the origin of epidemics prevailed. The first, taken from Hippocrates, held that environmentalfactorsdictated the potential for outbreaks and that an individual’s susceptibility determined whether he or she would fall ill. Dr. Mohammed Alnaif

17. History of Public Health History of Public Health The opposing theory of contagion, championed by Giolamo Fracastoro (1478 – 1533), evolved into our present understanding of infection. Fracastorobelieved microscopic agents were responsible for disease and that these agents could be transmitted by direct contact, through the air, or by intermediate fomites (inanimate objects such as doorknobs or drinking glasses that harbor infectious disease). Dr. Mohammed Alnaif

18. History of Public Health History of Public Health Giolamoand his contemporaries did not imagine these infectious agents to be alive, however; It was not until AntonvonLeeuwenhoek (1632 – 1723) observed the first microscopic organisms that people believed this to be possible. Despite earlier conjecture by some leading scientists, the germ theory of disease did not truly take hold until the late nineteenth century. Dr. Mohammed Alnaif

19. History of Public Health History of Public Health As mercantilism and the conquest for wealth and power swept Europe from the sixteenth to eighteenth centuries, public health progress was part of each nation’s interest. The necessity to quantify people and their health became clear. William Petty (1623 – 1687) coined the term politicalarithmeticand advocated the collection of data on income, education, and health conditions. (Gottfried Achenwallintroduced the term statisticsto replace political arithmetic in 1749.). Dr. Mohammed Alnaif

20. History of Public Health History of Public Health It was John Graunt (1620 – 1674), however, who published one of the first statistical analyses of a population’s health, noting associations between demographic variables and disease. Graunt wrote the Bills of Mortalityat the end of the seventeenth century. Based on the Bills of Mortality (what we would today call death records) he gathered from parishes in London and Hampshire, Graunt attempted to draw some conclusions about matters of life and death. Dr. Mohammed Alnaif

21. History of Public Health History of Public Health Grauntalso produced the first calculations of life expectancy. It was during this time that people began to recognize the need for state-supported programs to prevent premature (early) death. As France led the world into the Age of Enlightenment in the eighteenth century, public health began in earnest. A humanitarian spirit and the desire for equality led to a socialunderstanding of health. Dr. Mohammed Alnaif

22. History of Public Health History of Public Health Infant mortality was high on the list of concerns and disparities. Health education became popular, in line with the Enlightenment tenets of universal education and information dissemination. Despite earlier interest in the relationship of environment, social factors, and disease, it was in this era that health surveys were first employed. Dr. Mohammed Alnaif

23. History of Public Health History of Public Health Variolation (deliberate infection with smallpox), a common practice originating in China and spreading through the East over the centuries, became popular in the West in the 1700s. Although somewhat effective at preventing a serious case of disease, the practice of exposing susceptible people to smallpox could also induce severe forms of the disease and contributed to epidemics. Dr. Mohammed Alnaif

24. History of Public Health History of Public Health In 1798, Edward Jenner (1749 – 1823) used naturally acquired and fairly benign cowpox to inoculate against smallpox. Within three years, more than one hundred thousand people were vaccinated in England alone. As early as 1800, publications heralded the impending eradication of smallpox, an event that would be officially achieved in 1980. Dr. Mohammed Alnaif

25. History of Public Health Industrial Revolution and Victorian Era As the Industrial Revolution (between 1700 and 1900) spread from England through Europe and eventually to the United States, the health of workers quickly deteriorated, and calls for improved public health measures followed. The industrialization process widened gaps in income, causing the number of individuals receiving financial assistance from local governments to increase beyond capacity. Two studies of infectious diseases that laid the foundation for classical epidemiology and used methods that are still part of our armamentarium. Dr. Mohammed Alnaif

26. History of Public Health Industrial Revolution and Victorian Era In 1846 there was an outbreak of measles in the Danish Faroe Islands. The physician, who investigated the epidemic Peter Ludwig Panum, determined: That there is a delay between the time of exposure and the development of the rash (Incubation Period). That the disease is transmitted by direct contact between infected and susceptible people and does not arise spontaneously or because of "miasma”. (Methods of Transmission) When people with the disease were infectious. (Capable of spreading the disease to others) Most importantly that previous exposure of measles protected people from subsequent attacks. (Natural Immunity) Dr. Mohammed Alnaif

27. History of Public Health Industrial Revolution and Victorian Era During an 1848 cholera (an acute diarrheal illness) outbreak in London, John Snow (1813 – 1858), often deemed the father of epidemiology, identified a particular public water pump as the likely source of the epidemic. John Snow investigated the cause of the increased rate of cholera in London. He observed that the disease was most prevalent in districts supplied with water by certain companies that obtained there water from a section of Thames River that was extremely polluted with sewage. Dr. Mohammed Alnaif

28. History of Public Health Industrial Revolution and Victorian Era He also noted that the rate of new cases of cholera declined in those households supplied by the Lambeth Company after it relocated its intake pipe to a less polluted part of the Thames River. At the same time there was no change in the incidence of the disease in homes supplied by other companies that continued to draw its water from the heavily polluted section of the river. Dr. Mohammed Alnaif

29. History of Public Health Industrial Revolution and Victorian Era In 1834, Edwin Chadwick (1800 – 1890) led the development of England’s Poor Law Amendment Act Disease outbreaks were associated with the poorest, dirtiest parts of cities, but quickly began to affect all social classes. Chadwickunderstood the poverty – disease cycle and sought statistics to quantify the relationship. Chadwicklinked disease and the environment and called for city engineers, rather than physicians, to wage the war on disease outbreaks. Dr. Mohammed Alnaif

30. History of Public Health Industrial Revolution and Victorian Era The explosion of vital statistics (birth and death records) and survey data collection during this period prompted the publication of several data - based health reports during the mid - 1850s. There were no standards for analysis, however, and few authors employed the same methods, citing the inapplicability of mathematics to health. Adolphe Quetelet (1796 – 1874) began the work necessary to remedy the perceived incompatibility and published a compendium of practical applications of mathematics in health, what is called todaybiostatistics. Dr. Mohammed Alnaif

31. History of Public Health Industrial Revolution and Victorian Era During the nineteenth century, two theories relating to communicable (contagious or infectious) disease prevailed. The first was the miasma theory, which held that disease was due to a particular state of the air or environment. The second theory was that a specific contagion was responsible for each disease. In fact, many people believed some combination of the two was the real explanation: some contagious agent, whether disease specific or not, in combination with social or environmental factors, produced disease. By the end of the century, the germ theory of disease had been firmly established by Koch, Pasteur, and many others. Dr. Mohammed Alnaif

32. History of Public Health Industrial Revolution and Victorian Era From 1880 to 1898, the causative agents for a multitude of diseases, from malaria to tuberculosis and plague to typhoid were identified. Antiseptics became popular in medical care, which resulted in a marked decrease in morbidity (the existence of any form of disease, or to the degree to which the health condition affects the patient) and mortality (susceptibility to death). A more complete understanding of immunity was established late in the nineteenth century, and the development of vaccines proceeded nearly as rapidly as the discovery of pathogenic organisms. Dr. Mohammed Alnaif

33. History of Public Health Industrial Revolution and Victorian Era The United States Marine Hospital established one of the first bacteriological laboratories in the world in 1887. Although the United States was not the site of most scientific discovery in the era, it was the leader in applying new knowledge to public health. Throughout the 1900s, public health achievements such as water fluoridation, mass immunizations, motor vehicle safety, occupational safety, food supply safety and fortification, improved maternal and child health, family planning, prevention of heart disease and stroke, and, of course, control of infectious diseases led to substantially reduced morbidity and mortality Dr. Mohammed Alnaif

34. History of Public Health Modern Public Health Public health, and its tenets and activities, has evolved throughout time in response to shifts in societies’ values and scientific knowledge. Some of the historical issues of infectious diseases, health disparities, and population assessment continue to be modern public health challenges. There are new public health challenges also: populations are more mobile than ever, heightening concerns about pandemics. Dr. Mohammed Alnaif

35. History of Public Health Modern Public Health The mortality of many vaccines - preventable diseases declined so dramatically over the course of the twentieth century that often there is complacency about these diseases, and immunization rates have dropped. Antibiotic resistance has also made the apparent victory over common infections less certain. Medical care and insurance continues to cost more than many people can afford. . Bioterrorismand natural disasters have required planning for mass immunization, prophylaxis, evacuation, and treatment. Dr. Mohammed Alnaif

36. Introduction to Public Health Hallmarks of Public Health Although the issues facing public health may vary over time, the underlying principles of public health remain constant. There are three hallmarks of public health that define the field and also provide a contrast to the related field of medicine. Public health and medicine often have the similar goals of reducing the impact of disease and improving health and quality of life, but there are some notable differences between the two in the methods of reaching these goals. The hallmarks of public health are a philosophy of social justice, a focus on populations, and a focus on prevention. Dr. Mohammed Alnaif

37. History of Public Health Philosophy of Social Justice The term social justice has been used by various groups in different contexts. In public health, the concept of social justice connotes the idea that all individuals in a population should have access to the same programs and services, regardless of social condition or standing. This is in contrast to a concept of access to goods, services, and programs based on market forces, a concept known as market justice. Public health seeks to provide a basic level of health provisions, such as clean food and water, safe neighborhoods, and access to health care services, to all members of a community or population. In this vein, public health works to ensure there are no health disparities. Dr. Mohammed Alnaif

38. History of Public Health Focus on Populations In medicine, patients typically are seen and managed individually. In public health, the focus is on groups of people or populations rather than on individuals. Public health endeavors to implement programs that benefit a group of people: water fluoridation, folic acid fortification of grain products, the development of safe walking trails throughout a city, etc. Dr. Mohammed Alnaif

39. History of Public Health Focus on Populations Ultimately, these public health interventions will impact individuals ’ health, but the needs, desires, and attributes of the population as a unit are considered when making decisions in public health, rather than what will benefit each individual person. Public health focuses on prevention and the numerous efforts to prevent people from being exposed to harmful or unhealthful substances or experiences. Dr. Mohammed Alnaif

40. History of Public Health Focus on Prevention Indeed, public health focuses on preventing poor health outcomes or exposures that lead to these outcomes, and this focus is a hallmark of the field. Prevention has multiple levels, some of which may surprise you. Public health seeks to identify risk factors for disease and then works to learn methods for eliminating or limiting these risk factors to prevent populations from becoming ill or experiencing poor health. In addition, public health typically aims to maintain health rather than to address decrements in health after they have occurred. Dr. Mohammed Alnaif

41. History of Public Health Core Public Health Disciplines Although public health is a multidisciplinary field comprising individuals who may not have formal training in the subject, there are five core disciplines within public health in which practitioners are trained: epidemiology, biostatistics, social and behavioral sciences, environmental health, and health management and policy (Figure 1.2). Dr. Mohammed Alnaif

42. (Figure 1.2) Core Public Health Disciplines Epidemiology Health Management and Policy Biostatistics Public Health Social and Behavioral Sciences Environmental Health Dr. Mohammed Alnaif

43. History of Public Health Core Public Health Disciplines Epidemiology is the study of the determinants and distribution of health outcomes. It encompasses describing health outcomes based on the frequency or number of events and analyzing health outcomes to identify risk factors. Epidemiology may be divided into the two broad areas of chronic disease and infectious disease epidemiology. Biostatisticsprovides the tools to understand public health data. It is a branch of statistics devoted to understanding health and health outcomes and allows the analysis of complex studies. Dr. Mohammed Alnaif

44. History of Public Health Core Public Health Disciplines Environmental health is largely concerned with the impact of various exposures on health. Environment is broadly defined and may include any aspect of the physical environment and its relationship to health outcomes. Social and behavioral sciences focus on individual - level factors and the impact of external factors on health, primarily the influence of the social environment. This discipline includes understanding how people respond to external messages and information and how to change behavior (Health Education). Dr. Mohammed Alnaif

45. History of Public Health Core Public Health Disciplines Health management and policy is the discipline most concerned with issues of health care access and the policies at various levels of an organization or government, as well as how these policies impact health outcomes. Although each discipline has specialty skills and techniques for conducting its part of public health research and practice, public health education also includes cross - disciplinary training. This cross - training allows professionals in different disciplines to work together to solve problems that benefit from the application of more than one set of skills. Dr. Mohammed Alnaif

46. History of Public Health Core Public Health Disciplines Modern public health training programs typically include each of these disciplines in their master’s of public health (MPH) degree program. For more information about how public health training programs are organized and the competencies of these disciplines, visit the Council on Education in Public Health Web site, http://CEPH.org/. Dr. Mohammed Alnaif

47. THANK YOU Dr. Mohammed Alnaif