Epidemiology Chp. 1 Exam 1

  1. 1) What are the root words of epidemiology and what do they mean? 

    2) What is epidemiology?
    1) epi meaning “on or upon”, demos meaning “people” and logos meaning “the study of” 

    2)The study of the distribution and the determinants of health related events in a specified population, and the application of this study to the control of health problems.
  2. What are the major areas of epi and describe each?
    • Frequency - Number of events/ rate or risk of disease
    • Quantification- central activity counting cases

    Distribution- occurrence of events (i.e., time, place, demographics)  

    Determinants - factors causing health event how and why by comparing groups

    Application - provides data to direct public health action 
  3. Epidemiology is often referred to as _______. 
    population health 

    because it is concerned with groups and not individuals. 
  4. Epidemiology translate data into _____ and ____ into ________. 
    • Blank One: information 
    • Blank Two: information 
    • Blank Three: Action
  5. List at least five fields that epidemiology relies on. 
    • 1- Biostatistics 
    • 2-Genetics
    • 3- Clinical Medicine 
    • 4-Virology
    • 5- Pathology
  6. Define Morbidity and Mortality
    • Morbidity- health illness
    • Mortality - death
  7. What are the four aims of Epi? 
    • 1- Describe- health status of population
    • 2- Explain - etiology of disease
    • 3- Predict - the occurrence of disease
    • 4- Control - the occurrence of disease
  8. List at least five areas that epi investigates. 
    • 1. Chronic illness
    • 2. Injury
    • 3. Communicable/Infectious Diseases
    • 4. Disability
    • 5. Neonatal 
    • 6. Drug Addition
    • 7. Suicide 
  9. Define Epidemic. 
    The occurrence in a community or region of cases of an illness ( or an outbreak) clearly in excess of expectancy

    Relative to usual frequency of the disease
  10. Under what conditions can you classify the occurrence of an epidemic? 
    1 - A single case of a long absence communicable disease

    2- First invasion of a communicable disease

    3- Two cases of a communicable disease associated in time and place
  11. Define endemic. 
    The normal rate of disease. The expected levels seen over time. The background level of disease. 
  12. Define pandemic. 
    An epidemic on a worldwide scale. Example the flu pandemic. 
  13. How do health officials determine epidemics? 
    Surveillance and an epidemic threshold
  14. What is surveillance?
    A systemic method of collecting data relating to a disease occurrence. Analysis and interpretation of the data and dissemination of disease related information
  15. What is an epidemic threshold? 
    The minimum number of cases/deaths that indicates an epidemic occurrence. 
  16. What is a holoendemic? 
    A disease that basically all of the population acquires, usually during childhood. Controlled by vaccinations. 
  17. Define Incidence. 
    The number of new cases that occur during a certain timeframe. 
  18. Define Cumulative Incidence. 
    • The rate of development of disease over time. 
    • Number of new cases  X Time
    • Population at risk 

    Time= the period the cases occur
  19. What is the attack rate? 
    Alternative form of incidence. Used when disease occur of a short period of time. 

    Not true rate because time unknown

    • AR =       ill         X 100 (during time period) 
    •         ill + well 
  20. Define prevalence. 
    Number of existing cases (TOTAL) at a certain time
  21. What is the relationship between prevalence and incidence? 
    Prevalence (P) of disease is proportional to the incidence rate (I) times the Duration (D) of the disease. 
  22. True or False. 

    If the duration of the disease is short the prevalence becomes similar to incidence.

    Example common cold
  23. True or False
    If duration of disease is long and incidence is high, prevalence increases greatly relative to incidence.

    • If duration of disease is long and incidence is 
    • low, prevalence increase greatly relative to incidence.

    Example chronic diseases
  24. Explain the basic triangle model. 
    This model illustrates the interaction between the host, agent, and environment. 
  25. Explain the advanced triangle. 
    The interactions between the population, causative factors, and social/physical environment. 
  26. Explain the wheel model. 
    • Inner most circle - intrinsic
    • Middle circle - host
    • Outer most circle - extrinsic 
  27. Explain the single agent- single disease model. 
    For a disease there is only one causing factor/agent. 

    Example: Hiv(agent) -> AIDS (disease)
  28. Explain multifactorial etiology. 
    Multiple factors cause a disease. 

    • Example
    • Factors: diet, physical activity, stress, smoking, high blood pressure

    Disease: Heart Disease
  29. Explain the web of causation. 
    Multiple factors can cause multiple diseases. 

    • Example
    • Diet > Cancer, Stroke, Heart Disease 
    • Smoking > Heart Disease, Stroke, Cancer
    • Stress > Heart Disease, Stroke
  30. Explain the Holistic Model. 
    • All of this elements affect the host
    • Host > biological, environment, life style, and health care system
  31. What are the portals of entry for each. 
    auditory canal
    • respiratory: particulates, aerosols
    • oral/gastrointestinal: ingestion 
    • reproductive: STIs anus, vagina, penis
    • skin: cut/follicles/absorb
    • intravenous: drugs contaminated blood products
    • auditory canal:ear infections
    • transplacental: HIV, chemicals, drugs
    • cardiovascular: plaque 
    • conjunctival: eye
  32. How do agents cause disease? 
    • 1. Interferes with normal body function (cancer)
    • 2. Cause reaction (inflammation)
    • 3. Destory tissue/organ function (ie stroke, AIDS)
  33. What are the measures of disease severity?
    • Inapparent: no signs or symptoms
    • Mild: signs or symptoms (S&S) but able to fucntion normally
    • Moderate:S&S, not functioning normally, but not under medical care
    • Severe: S&S, not functioning, under medical care
    • Fatal: RHC respirations have ceased
  34. Explain infectivity. 
    the capacity of the agent to enter and multiply in a susceptible host an thus produce infection or disease

    • Secondary Attack Rate
    • new cases/ susceptible exposures
  35. Explain pathogenicity. 
    capacity of the agent to cause disease in the infected host. 

  36. Explain Virulence
    the severity of the disease, the ability to cause severe or fatal cases if the person becomes ill. One measure of virulence is the proportion of the total cases that are severe. 

  37. Explain Case Fatality. 
    ability to cause death if the person becomes ill. 

  38. Explain immunogenicity.
    ability of agent to induce antibody production in the host. Refers to an infectious agent ability to produce a specific immunity and protect against re-infection. 
  39. Explain antigenicity. 
    ability of agent to induce antibody production in the host. A related term immunogencity which refers to an infectious agents ability to produce a specific immunity. 
  40. Explain Resistance.
    The ability of the agent to survive in adverse conditions-environmental, medications, etc. Can also apply to the host
  41. Explain toxigenicity. 
    capacity of the agent to produce a toxin or posion. Pathologic effects for agents such as botulims, E. coli, result form the toxin produced by the micro-organism rather than the micro-organism itself. 
  42. List and explain body defenses. 
    Barriers and Secretations: skin, stomach acidic, mucus

    Natural Flora: normal microbial flora provides checks and balances 

    Inflammatory Response: Swelling/edema, elevated temperature

    Reticuloendothelial system (RES): clears micro-organisms from the blood. lymph systems
Card Set
Epidemiology Chp. 1 Exam 1
Epidemiology Chapter One Review