Epidemiology Past Paper PDF

Course Title: Epidemiology Course code: NSC: 301  Hx of epidemiology CONTENTS Origins of epidemiology Definitions of epidemiology Objectives ‘’ ‘’ Branches ‘’ ‘’ Timeline John Graunt the first epidemiologist James Lind and Scurvy  Edward Jenner and smallpo...

Course Title: Epidemiology Course code: NSC: 301  Hx of epidemiology CONTENTS Origins of epidemiology Definitions of epidemiology Objectives ‘’ ‘’ Branches ‘’ ‘’ Timeline John Graunt the first epidemiologist James Lind and Scurvy  Edward Jenner and smallpox John Snow and Cholera Ignaz Semmelweis and childbed fever  ORIGIN OF EPIDEMIOLOGY Epidemiology is derived from the greek word epidemic Epi - ON, OR UPON OR AMONG Demos – which means the common people Logy – which means study of The study of that which falls upon the common people  Epidemiology is a branch of medicine that deals with the scientific, data- driven study of the incidence, distribution (frequency, pattern), determinants (causes, risk factors) and possible control of diseases and health-related events in specific populations (neighbourhood, city, state, country, global).  DEFINITIONS OF EPIDEMIOLOGY The part of medical science which treats epidemics. Parkin 1873 The science of the mass phenomena of infectious diseases Frost ,1927 The study of disease, any disease as a mass phenomenon Greenwood ,1934 The study of distribution and determinants of disease frequency in man MacMahon,1960  DEFINITIONS OF EPIDEMIOLOGY CONT’D The study of distribution and determinants of Health related states or events in specified populations and application of this study to control of health problems John M. Last 1988 The study of how disease is distributed in populations and the factors that influence or determine this distribution  OBJECTIVES OF EPIDEMIOLOGY To understand the cause or etiology of a disease and the relevant risk factors; To determine the extent of disease found in the community; To study the natural history and prognosis of disease; To evaluate preventive and therapeutic measures and modes of health care delivery  OBJECTIVES OF EPIDEMIOLOGY CONT’D To provide the foundation of developing public health policies  BRANCHES OF EPIDEMIOLOGY Infectious disease epidemiology Chronic ‘’ ‘’ Clinical epidemiology Serological ‘’ Cancer ‘’ Genetic ‘’ Occupational ‘’ Psychosocial ‘’  HX OF EPIDEMIOLOGY The Greek physician Hippocrates is known as the father of medicine, and was the first epidemiologist. Hippocrates sought a logic to sickness. He is the first person known to have examined the relationships between the occurrence of disease and environmental influences.  Hippocrates believed sickness of the human body to be caused by an imbalance of the four Humors (air, fire, water and earth “atoms”). The cure to the sickness was to remove or add the humor in question to balance the body. This belief led to the application of bloodletting and dieting in medicine.  HX CONTD The distinction between “epidemic” and “endemic” was first drawn by Hippocrates, to distinguish between diseases that are “visited upon” a population (epidemic) from those that “reside within” a population (endemic). The term “epidemiology” appears to have first been used to describe the study of epidemics in 1802 by the Spanish physician Joaquín de Villalba in Epidemiología Española.  HX CONTD One of the earliest theories on the origin of disease was that it was primarily the fault of human luxury. This was expressed by philosophers such as Plato and Rousseau, and social critics like Jonathan Swift.  In the middle of the 16th century, a doctor from Verona named Girolamo Fracastoro was the first to propose a theory that these very small, unseeable, particles that cause disease were alive. They were considered to be able to spread by air, multiply by themselves and to be destroyable by fire.  Hippocrates believed sickness of the human body to be caused by an imbalance of the four Humors (air, fire, water and earth “atoms”). The cure to the sickness was to remove or add the humor in question to balance the body. This belief led to the application of bloodletting and dieting in medicine.  HX CONTD In 1543,Girolamo wrote a book De contagione et contagiosis morbis, in which he was the first to promote personal and environmental hygiene to prevent disease. The development of a sufficiently powerful microscope by Anton van Leeuwenhoek in 1675 provided visual evidence of living particles consistent with a germ theory of disease.  HX CONTD Dr. John Snow is famous for his investigations into the causes of the 19th century cholera epidemics, and is also known as the father of (modern) epidemiology He used chlorine in an attempt to clean water thus ending the outbreak. This has been perceived as a major event in the history of public health and regarded as the founding event of the science of epidemiology, having helped shape public health policies around the world.  However, Snow’s research and preventive measures to avoid further outbreaks were not fully accepted or put into practice until after his death.  In the middle of the 16th century, a doctor from Verona named Girolamo Fracastoro was the first to propose a theory that these very small, unseeable, particles that cause disease were alive. They were considered to be able to spread by air, multiply by themselves and to be destroyable by fire.  In the early 20th century, mathematical methods were introduced into epidemiology by Ronald Ross, Anderson Gray McKendrick and others. Another breakthrough was the 1954 publication of the results of a British Doctors Study, led by Richard Doll and Austin Bradford Hill, which lent very strong statistical support to the suspicion that tobacco smoking was linked to lung cancer.  Epidemiology has evolved over time from focusing on infectious diseases and epidemics in 1800 to applying observational scientific method to prevent and control health related states and events.  TIMELINE 3rd century BC- Greek word epidemic 1662- John Grant became the first epidemiologist, statistician and demographer 1747- James Lind conducted the first ever clinical trial and concluded that citrus fruits cure scurvy 1796- Edward Jenner performed first vaccination  TIMELINE CONT’D 1849- John Snow published “The mode of communication of cholera 1850s- epidemiological society of London TIMELINE CONT’D KEY TERMS IN EPIDEMIOLOGY Health: a state of complete physical, mental, and social well-being and not merely the absence of disease (WHO, 2020). Public Health: Organized community effort to prevent disease and promote health Illness: what a person physiologically or psychologically experiences. Disease: a medically definable physiological or psychological dysfunction. Sickness: the state of dysfunction of the social role of a person with disease.  Mortality: related to death. Morbidity: events and factors associated with disease or disability. Endemic: disease and injuries occurring at a consistent rate Epidemic: the occurrence of disease or injuries in clear excess of normalcy. Pandemic: a epidemic that affects several countries or continents  KEY TERMS CONTD Frequency: the number disease/injury events in a population and the rate or risk of disease in the population. Rates are critical for making valid comparisons across different populations. Pattern: the occurrence of health-related events by time, place, and personal characteristics.  KEY TERMS CONTD Time: includes annual occurrence, seasonal occurrence, and daily or even hourly occurrence during an epidemic. Place: includes geographic variation, urban- rural differences, and location of worksites or schools. Personal characteristics include demographic factors such as age, race, sex, marital status, and socioeconomic status, as well as behaviors and environmental