Intro to Epidemiology

• Specified Populations


  Examine occurrence of health-related states or events in populations rather than among individuals (“population medicine”)
• Epidemiology


  • Studies the patterns of disease occurrence in human populations and the factors that influence this pattern
  • Basic science of public health and medicine
• Epidemic


  Derived from the Greek word “epi” and “demos” & “logos”, meaning "Upon the people and leading the people"
• Distribution


  Refers to the analysis of health-related states or events in terms of person, place, and time characteristics
• Epidemiology


  Study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the prevention and control of health problems
• Determinants


  • Biological
  • Chemical
  • Physical
  • Social
  • Cultural
  • Economic
  • Genetic
  • Behavioral
• Ancient Greeks had early explanations for disease such as wrath of gods, evil spirits, religious beliefs, and weather. Treatment included praying to good spirits, offering sacrifices, and building to purify the air

  400 BC
• John Graunt used quantitative methods to describe vital population statistics


  1669
• Ignas Semmelweis, known as the Father of Handwashing, pioneered antiseptic procedures and investigated mortality rates from childbed fever


  1840
• John Snow, the Father of Modern Epidemiology, investigated the source of a cholera outbreak using modern field epidemiology methods


  1849-1854
• Robert Koch, known for the "Germ/Bacteriological" theory, postulated the causes of diseases by specific living organisms


  1884
• Framingham Study started in 1949
• Explosion of investigation of disease occurrences and development of epidemiologic methods for noncommunicable diseases

  1990s
• Disease causation


  • Something that brings about an effect
  • An event, condition, characteristic or a combination of these factors which has a role in producing the health outcome
• Disease causation


  Process by which disease occur and progress in the human body
• British Doctor Study


  • Enrolled thousand British male doctors
  • Provided strong evidence linking smoking to lung cancer
• Microorganisms must be observed in, and recovered from the experimentally diseased animals
• Framingham Study


  • Started in 1949
  • Recruited disease-free men and women
  • Initial medical history and physical exam, follow-up every 2 years
  • Provide evidence in identification of risk factors for cardiovascular heart diseases (blood pressure, cholesterol, smoking, activity level)
  • Advance the design and implementation of longitudinal studies
• Germ Theory of Disease


  States that specific microscopic organisms are the cause of specific diseases
• Exposure triggers the disease process to start
• Associations between a suspected cause and outcome should not be used as factual basis for disregarding possible risk factors
• Natural History of Disease is the progression of a disease process in an individual over time, in the absence of treatment
• Specificity of the association is the weakest of all guidelines and should probably be deleted from the list
• Susceptibility factors include behaviors that increase opportunity for exposure, poor health and nutrition, lack of immunity
• Subclinical stages of diseases are stages before diagnosis
• Adaptation is the immune system response
• Classification of diseases is a method of grouping diseases based on their specific features, following a standard set of principles
• International Classification of Diseases (ICD) is a diagnostic classification standard for all clinical and research purposes used by more than 100 countries worldwide
• Epidemic is the study of the distribution and determinants of health related states, and studies the pattern of disease occurrences. Basic science of health and medicine.
• Health related states refer to specific health outcomes (disease, disability, death)
• Distribution refers to the analysis of health related states, and is the frequency number of health relative to population size
• Specified population is examinee occurrence of health related state or events in populations rather than among individuals "population medicine"
• Who is the father of medicine?

  Hippocrates
• Give 3 physical environment factors influencing disease?

  Changing the season, hot cold wind, qualities of water
• Who is the first to discover regularities in morality and uses quantitative methods in describing vital population statistics (counting of births & deaths)?

  John Graunt
• Who is the father of handwashing and pioneer to antiseptic procedures, and investigated why mortality rate was higher in the clinic for medical students than that for midwives?

  Ignas Semmelweis
• Who is the father of modern epidemiology?

  John Snow
• What are the 2 service companies denotes high cholera rates that Snow notes in districts?

  Lambeth company, Southwark & Vauxhall company
• Who is known for "Germ/Bacteriological" Theory?

  Robert Koch
• What study provide evidence in identification of the risk factors for cardiovascular heart diseases?

  Framingham Study