Epidemiology - Midterm (Everything =C
)
Study online at https://quizlet.com/_hpg6x2
1. Epidemiology: The study of the determinants of health and diseases in populations with the goal of prevention
2. Takeaway of John Snow & The Cholera Epidemic: Able to prevent spread of cholera without
even understanding what cholera was and how it's transmitted
3. Takeaway of Semmelweiss & Cadaverous Poisoning: Semmelweiss very poorly communi-
cated that hand-washing would disrupt transmission
4. Underlying Principle of Epidemiology: Disease does not occur randomly in populations; there are
reasons
5. Does Disease Occur Randomly in Populations?: No
6. Why Are Some More Likely to Develop Disease?: Differences in "exposure" to the "cause" of
disease
7. Epidemiological Approach: Describe current status, look for patterns in populations, make comparisons
between groups, describe changes over time, establish causation
8. Primary Prevention: Preventing exposure
9. Secondary Prevention: Detection of disease
10. Tertiary Prevention: Therapy (treatment)
11. Epidemiologic Triad: Agent, host, and environment
12. Function of Epidemiological Triad: Framework to understand relationship of agent, host, and
environment in health and disease
13. Important Agent Factors: Infectivity, pathogenicity, virulence
14. Important Environmental Factors: Temperature, stocking density, air and water quality
15. Important Host Factors: Genetics, immune status, nutrition
16. Types of Agents: Biological, physical, chemical
17. Potential Causes of Sudden Death in Horses: Blue-green algae, dry water sources, lightning
strike, arsenic toxicosis, blackleg, nitrite poisoning, anthrax
18. Evidence-Based Medicine: The integration of individual clinical expertise with the best available exter-
nal clinical evidence from systematic research
19. Natural History of Disease: Pattern of disease progression
20. Spectrum of Disease: No infection -< subclinical infection-> clinical disease -> cure, control, disability, or
death
21. Chain of Infection: Etiologic agent, reservoir, portal of exit, mode of transmission, portal of entry, suscep-
tible host
22. Important Information About Etiologic Agent: Infectivity, pathogenicity, virulence
, Epidemiology - Midterm (Everything =C
)
Study online at https://quizlet.com/_hpg6x2
23. Infectivity: Ability of an organism to multiply in host
24. Infectivity is Seen as: Seroconversion, secondary attack rate
25. Pathogenicity: Ability of agent to cause disease
26. Pathogenicity is Seen as: Attack rate
27. Attack Rate =: Number affected/number at risk
28. Virulence: Ability of agent to cause severe disease/death
29. Virulence is Seen as: Case fatality
30. Reservoir: Ecological niche where a pathogen lives and multiplies
31. Carrier: Subclinical source of agent
32. Reservoir vs. Carrier: Reservoirs are usually needed to perpetuate the agent, while carriers aren't
33. Examples of Reservoirs: Coccidioides immitis in environment, Dengue in humans
34. Examples of Portals of Exit: Conjunctiva, mouth, anus, urogenital tract, blood
35. Examples of Portals of Entry: Conjunctiva, mouth, inhalation, urogenital tract, skin, arthropod,
scratch/injury
36. Examples of Modes of Transmission: Direct or indirect contact, droplet/aerosol/vector/vehicle,
horizontal or vertical
37. Vector: Transmits infection from one susceptible individual to another
38. Biological Vector: Essential to pathogen life cycle
39. Mechanical Vector: Not essential to pathogen's life cycle
40. Vehicle: Fomite; may be biological as well
41. Iceberg Analogy: When we see clinical disease, there is likely much more subclinical disease and even
more exposure without infection
42. Clinical vs. Subclinical Disease: Clinical has obvious signs, whereas subclinical is likely only detected
by diagnostics
43. Typical Epidemic Curve: Number of cases on vertical axis, time on horizontal
44. Endemic Disease Occurs With: Predictable regularity
45. Epidemic Disease Occurs With: Disease exceeding expectations
46. Epidemic vs. Pandemic: Epidemic is confined to one area, while pandemic is over multiple continents
47. Sporadic Disease Occurs With: Rarity and no regularity
48. Incubation Period: Time of infection to time of clinical disease
49. Latent Period: Time of infection to time animal is infectious
50. Lowest Bar of Ladder of Evidence: Expert opinion, anecdote, case report
)
Study online at https://quizlet.com/_hpg6x2
1. Epidemiology: The study of the determinants of health and diseases in populations with the goal of prevention
2. Takeaway of John Snow & The Cholera Epidemic: Able to prevent spread of cholera without
even understanding what cholera was and how it's transmitted
3. Takeaway of Semmelweiss & Cadaverous Poisoning: Semmelweiss very poorly communi-
cated that hand-washing would disrupt transmission
4. Underlying Principle of Epidemiology: Disease does not occur randomly in populations; there are
reasons
5. Does Disease Occur Randomly in Populations?: No
6. Why Are Some More Likely to Develop Disease?: Differences in "exposure" to the "cause" of
disease
7. Epidemiological Approach: Describe current status, look for patterns in populations, make comparisons
between groups, describe changes over time, establish causation
8. Primary Prevention: Preventing exposure
9. Secondary Prevention: Detection of disease
10. Tertiary Prevention: Therapy (treatment)
11. Epidemiologic Triad: Agent, host, and environment
12. Function of Epidemiological Triad: Framework to understand relationship of agent, host, and
environment in health and disease
13. Important Agent Factors: Infectivity, pathogenicity, virulence
14. Important Environmental Factors: Temperature, stocking density, air and water quality
15. Important Host Factors: Genetics, immune status, nutrition
16. Types of Agents: Biological, physical, chemical
17. Potential Causes of Sudden Death in Horses: Blue-green algae, dry water sources, lightning
strike, arsenic toxicosis, blackleg, nitrite poisoning, anthrax
18. Evidence-Based Medicine: The integration of individual clinical expertise with the best available exter-
nal clinical evidence from systematic research
19. Natural History of Disease: Pattern of disease progression
20. Spectrum of Disease: No infection -< subclinical infection-> clinical disease -> cure, control, disability, or
death
21. Chain of Infection: Etiologic agent, reservoir, portal of exit, mode of transmission, portal of entry, suscep-
tible host
22. Important Information About Etiologic Agent: Infectivity, pathogenicity, virulence
, Epidemiology - Midterm (Everything =C
)
Study online at https://quizlet.com/_hpg6x2
23. Infectivity: Ability of an organism to multiply in host
24. Infectivity is Seen as: Seroconversion, secondary attack rate
25. Pathogenicity: Ability of agent to cause disease
26. Pathogenicity is Seen as: Attack rate
27. Attack Rate =: Number affected/number at risk
28. Virulence: Ability of agent to cause severe disease/death
29. Virulence is Seen as: Case fatality
30. Reservoir: Ecological niche where a pathogen lives and multiplies
31. Carrier: Subclinical source of agent
32. Reservoir vs. Carrier: Reservoirs are usually needed to perpetuate the agent, while carriers aren't
33. Examples of Reservoirs: Coccidioides immitis in environment, Dengue in humans
34. Examples of Portals of Exit: Conjunctiva, mouth, anus, urogenital tract, blood
35. Examples of Portals of Entry: Conjunctiva, mouth, inhalation, urogenital tract, skin, arthropod,
scratch/injury
36. Examples of Modes of Transmission: Direct or indirect contact, droplet/aerosol/vector/vehicle,
horizontal or vertical
37. Vector: Transmits infection from one susceptible individual to another
38. Biological Vector: Essential to pathogen life cycle
39. Mechanical Vector: Not essential to pathogen's life cycle
40. Vehicle: Fomite; may be biological as well
41. Iceberg Analogy: When we see clinical disease, there is likely much more subclinical disease and even
more exposure without infection
42. Clinical vs. Subclinical Disease: Clinical has obvious signs, whereas subclinical is likely only detected
by diagnostics
43. Typical Epidemic Curve: Number of cases on vertical axis, time on horizontal
44. Endemic Disease Occurs With: Predictable regularity
45. Epidemic Disease Occurs With: Disease exceeding expectations
46. Epidemic vs. Pandemic: Epidemic is confined to one area, while pandemic is over multiple continents
47. Sporadic Disease Occurs With: Rarity and no regularity
48. Incubation Period: Time of infection to time of clinical disease
49. Latent Period: Time of infection to time animal is infectious
50. Lowest Bar of Ladder of Evidence: Expert opinion, anecdote, case report
