Lecture 1: Introduction, History, and Definitions

• What is included in the LMU One Health Model

  Animal, Human, Environment and Social determinants of health
• The great epi detective cases:


  What, where, who, how, why, when?
• Who is the father of epidemiology?

  John Snow
• Broad Street, London had a major cholera outbreak in what year?

  1849
• Definition of health


  Health is a state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.
• Disease definition


  absence of health
• Definition of epidemiology


  the study of what is upon the people
• What is the LMU definition of epidemiology?

  The study of the health of populations
• Case definition


  standard set of criteria for deciding whether an individual has a particular health condition.
• Case definition can be

  sensitive, specific, influenced by number of cases
• The Centers for Disease Control and Prevention changed the case definition for acquired immunodeficiency disease (AIDS) in the United States between what years?

  1992-1993
• What is the CDC's definition of Epidemic or Outbreak?


  The occurrence of more cases of disease than expected in a given area or among a specific group of people over a particular period of time.
• True or False: An outbreak may occur in a restricted geographical area, or may extend over several countries.

  True
• True or False: an outbreak can also be a single case of a communicable disease long absent from a population, especially one of high mortality.

  True
• Definition of Pandemic


  an epidemic that becomes very widespread and affects a whole region, a continent, or the world due to a susceptible population.
• What is a true pandemic?

  associated with high morbidity and significant mortality.
• What is the formula for attack rate?


  # of new cases in population at risk/# of people in population at risk X 100= AR
• What is the crude mortality rate?

  is the mortality rate from all cases of death for a population during a specified time period.
• For crude mortality rate what is the denominator?


  the total population at the mid-point of the time period
• What is case fatality rate?

  The proportion of animals/persons with a particular condition who die from that condition
• What is the numerator for case fatality rate?

  # of deaths among those cases
• What is the denominator for case fatality rate?

  # of incident cases
• What is cause specific death rate?


  the # of deaths from a specific cause per person/animal-years at risk
• True or False CSDR is very similar to, but not completely synonymous with CFR


  True
• What is included in the epidemiologic triad?

  agent, host, environment, disease