Week 11 : Basic Concepts and Principles of Epidemiology

Cards (33)

  • Epidemiology - study of factors that determine the occurence and distribution of disease in a population
  • Epi - upon
  • Demos - population
  • Logos - study
  • Epidemiologists - deal with data from group of patients or even entire population
  • Classical Epidemiology
    • studies the distribution and determinants of disease in populations and the community origina of health problems
    • interested in discovering risk factor that might be altered in a population to prevent or delay disease, injury, and death
  • Clinical Epidemiology
    • application of principles of epidemiology to clinical medicine
    • clinical epidemiologists often study patients in health-care settings rather than in the community at large
  • Etiology - cause or origin of a disease or abnormal condition
  • Natural History - way a disease progresses in the absence of medical or public health intervention
  • Predisease - before the disease process begins
    Primary Prevention - preventing the disease process from starting
  • Latent - disease process has already begun but is still asymptomatic
    Secondary Prevention - screening for the disease and providing appropriate treatment that may prevent progression to symptomatic disease
  • Symptomatic - disease manifestations are evident
    Tertiary Prevention - disease manifestations are evident intervention may slow, arrest, or reverse the progression of disease
  • Agent
    • what of the triangle
    • whatever causes the disease
    four categories ;
    • biologic agents
    • chemical agents
    • physical agents
    • social and psychologic stressors
  • Host
    • who of the triangle
    • the person or organism harboring the disease
    • resistance is influenced by; genotype, nutritional status, body mass index, immune system and behaviour
  • Environment
    • where of the triangle
    • external factors that causes or allow disease transmission
  • Vectors
    • how of the triangle
    • serves as vehicles to transmit disease
    • include insects, arachnids, and mammals
    • to be an effective transmitter of disease, the vector must have a specific relationship to the agent, the environment, and the host
  • BEINGs Model - serve as mnemonic device for the major categories of risk factors for disease
    • Biologic factors and Behavioral factors
    • Environmental factors
    • Immunologic factors
    • Nutritional factors
    • Genetic factors
    • Services, Social factors, and Spiritual factors
  • Vaccination
    • herd immunity/population immunity - protects the immunized individual, but also prevents that person from transmitting the disease to others
    • indirect protection - from an infectious disease that happens when a population is immune either through vaccination or immunity developed through previous infection
  • Solution of Public Health Problems
    • vaccination
    • improved sanitation
    • vector control
    • erection of large river dams
  • Epidemiological Principles and methods are applied in
    • clinical research
    • disease prevention
    • health promotion
    • health protection
    • health services research
  • ultimate aim of epidemiology aims and objectives of epidemiology
    • to eliminate or reduce the health problems of community
    • to promote the health and well-being of society as a whole
  • Distribution
    • time, place, person
    • pattern - hypothesis for causative/risk factor = etiological hypothesis
    • descriptive epidemiology
  • Determinants
    • causes, risk factors, mode of transmission
    • how and why of disease
    • identifying the causes and risk factors for diseases
    • testing the hypothesis - biostatistics
    • analytical epidemiology
  • Scope of Epidemiology
    • causation of the disease
    • natural history of the disease
    • health status of the population
    • evaluation of interventions
  • Applications of Epidemiology in Public Health
    • preventing the diseasw and promoting health
    • community health assessment (community diagnosis) and priority setting
    • improving diagnosis, treatment, and prognosis of clinical diseases
    • evaluating health interventions and programs
  • Public Health - refers to collective actions to improve population health
  • Epidemiology - one of the tools for improving public health, is used in several ways
  • Epidemiology
    • unit of study - defined population or population at risk
    • concerned with the disease pattern in entire population
    • concerned with both sick and healthy
    Clinical Medicine
    • unit of study - case
    • physician is concerned with the disease in the individual patient
  • Epidemiology
    • epidemiologist is confronted with the relevant data derived from the particular epidemiological study (community diagnosis)
    • seek to identify the source of infection, mode of transmission, and an etiological factor to determine the future trends, prevention, and control measure
    Clinical Medicine
    • physician seeks to diagnosis for which he derives prognosis and prescribes specific treatment
  • Epidemiology
    • epidemiologists goes to the community to find out the disease pattern and suspected causal factors in the question
    Clinical Medicine
    • patient comes to the doctor
  • Epidemiological Approach
    • asking questions
    • making comparisons
  • 5 W’s
    • case definition - what
    • person - who
    • place - where
    • time - when
    • causes - why
  • Making Comparisons
    • find out the differences in the agents, host, and environment conditions between two groups
    • weighs, balances, and contrasts give clues to etiological hypothesis