Basic concepts and princi of epi

• Epidemiology

  • clinical epidemiology
  • classical epidemiology
• Epidemiology

  • study of factors that determine the occurence and distribution of disease in a population.
  • studies conducted among human population
• Classical epidemiology

  • studies the distribution and determinants of disease in populations and the community origins of health problems
  • interested in discovering risk factors to prevent or delay disease, injury, and death
• Clinical epidemiology

  • application to clinical medicine
  • often study patient’s in health care settings rather than in the community at large
• Etiology

  cause or origin of a disease
• Latent

  • secondary prevention
  • disease process has already begun but still asymptomatic
• Host

  • “who” of the triangle
  • persom or organism harboring the disease
  • resistance is influenced by: genotype, nutritional status, bmi, immune system and behaviour
• Agent

  • ”what” of the triangle
  • whatever causes the disease
  • 4 categories: biologic, chemical, and physical agents and social and psychologic stressors
• Environment

  • ”where” of the triangle
  • external factors that cause or allow disease transmission
• Vectors

  • ”how”
  • serves as vehicles to transmit disease
  • include insects, arachnids, et
• Hard/Population immunity

  • protects the immnized indiv, but also prevents that person from transmitting the disease to others
• Solution of public health problems

  • vaccination
  • improved sanitation
  • vector control
  • erection of large river dams
• Contributions of epidemiologists

  • investigating epidemics
  • studying the biologic spectrum of disease
  • surveillance
  • setting disease
  • improving diagnosis
  • improving health services
  • providing expert testimony
• Epidemiology

  • basic science of preventive and social medicine
• Ultimate aim of epi

  • eliminate or reduce the health problems of community
  • promote the health and well being of society as a whole
  • break the triangle
• Scope of epidemiology

  • causation of the disease
  • natural history of the disease
  • health status of the population
  • evaluation of interventions