Download 7 Epidemiology Flashcards

7 Epidemiology
1. What does symbiosis mean?
2. What are the 3 types of symbiosis?
3. What is mutualism?
4. What is an example of Mutualism?
5. What is commensalism?
6. What is an example of commensalism?
7. What is parasitism?
8. What is an example of parasitism?
9. What are Normal Flora?
10. What is an Opportunistic Pathogen?
11. In what ways to organisms
demonstrate Tissue Tropism?
12. What does HIV integrate?
13. Do obligate pathogens kill their host?
14. What is multiplicity of infection?
15. What is the relationship between
virulence and Multiplicity of Infection?
16. How many organisms can form an
innoculum in a virulent organism such as
anthrax?
17. How many organisms do most
innoculum need?
18. How does anthrax avoid immune
defense?
19. What is the role of mycobacterium?
20. What is the role of rickettsia?
To live together
Mutualism, Commensalism, and
Parasitism
Both organisms living together are
benefited, neither are harmed
Bacteria in human colon
One organism benefits and the other does
not benefit but is not harmed
staphylococcus on the skin (we are not
harmed, but we have no benefit)
One organism benefits, one is harmed
Tuberculosis (we are harmed)
Normal flora is when an organism is
always in or on us, GI, GU, oral
mucosa
A normal flora organism that becomes
a pathogen when the host’s immune
defense decreases.
Influenza does not affect your hand;
gonorrhea only effects mucosa.
Tropism can also be species, organ, or
non-specific
Integrates a provirus into our
chromosome
No
The number of organisms needed to
cause disease.
Inverse relationship
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103
By exploiting the very mechanisms used
to fight it. It becomes activated after
phagocytosis.
Coat the wall of vacuoles so lysozymes
can’t fuse.
On a timer, rickettsia escapes the vacuole
to invade the nucleus.
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7 Epidemiology
21. What are the portals of entry (POE)?
22. What are the modes of transmission
(MOT)?
23. A living organism that spreads disease
from one host to another
24. Inanimate object that spreads disease
from one host to another
25. A presence of an organism is known
as what?
26. Adverse symptoms due to infection
27. Organisms that are typically found on
a healthy individual
28. Organism causing disease (etiologic
agent)
29. Suppressed or deficient immunity
30. Acquired in hospital setting
31. Acquired in routine, day-to-day
activities
32. normal flora + compromised pathogen
33. always causes Dz if present
34. What does “normal microbiota”
mean?
35. What are 2 names that also mean
“normal microbiota”?
36. What are 2 types of normal microbiota
in hosts?
37. What is bacteremia?
Cephalic (7 portals): mouth, nose, eyes,
ears
Corporeal: mammary, vaginal, urethral,
rectal
Trauma/Medical: burn, compound
fracture, surgical/catheter, injury/IVDA,
abnormal mucosa (CA chemo)
AEROSOL: Airborne micro-particles
(soil aerosol containing endospores)
DROPLET NUCLEI: Mucoid microdroplet via cough or sneeze, durable on
surfaces, mainly transmitted by contact.
DIRECT CONTACT: Direct
object/tissue-to-tissue contact.
CASUAL TRANSMISSION:
handshake, clothing
ASPIRATION: inhalation or oral, GI,
or food-borne organisms
FECAL-ORAL: autoinoculation or
contamination (poor hygiene)
SEXUAL TRANSMISSION (STD):
sexual/bodily fluid contact
Vector
Fomite ( examples include toothbrush,
water glass, toys, handles)
Contamination
Disease
Normal Flora
Pathogen
Immunocompromised
Nosocomial
community acquired
opportunistic pathogen
Obligate pathogen
Organisms that colonize the body’s
surfaces without causing disease
1) Normal flora
2) Indigenous flora
1) Resident microbiota
2) Transient microbiota
Bacteria in the bloodstream
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7 Epidemiology
38. What is bacteruria?
39. What is a pyrogenic?
40. What is pyogenic?
41. What is pyemia?
42. What is a differential diagnosis?
43. What is urosepsis?
44. Of the 2 types of normal microbiota,
what type is part of the normal microbiota
throughout life?
45. Of the 2 types of normal microbiota,
what type remains in the body for a short
period of time?
46. What are 3 reasons why transient
microbiota cannot persist in the body?
47. When does microbiota start to develop
in the body?
48. When do much of one’s resident
microbiota establish?
49. What are opportunistic pathogens?
50. What is axenic?
51. What is one condition that can induce
normal microbiota to convert to
opportunistic pathogens?
52. Immune suppression can provide the
opportunity for normal microbiota to
convert into what type of pathogen?
53. Transient bacteria are found in the
same regions as __________ microbiota.
54. In regards to cell surface markers,
what does “CD” mean?
55. What are cell surface markers used
for?
56. Can pathogens survive a long time
outside of their host?
57. What is a “reservoir of infection?”
58. A(n) ______ reservoir is a type of
reservoir for infection.
59. What are 2 types of reservoirs?
Bacteria in urine
Fever-producing infection
Pus-producing
Gram + bacteremia
All possible causes of the disease
Septicemia from UTI
Resident microbiota
Transient microbiota
1) Competition from other
microorganisms
2) Elimination by the body’s self-defense
cells
3) Chemical or physical changes in the
body
During the birthing process
During the first months of life
Normal microbiota that cause disease
under certain circumstances
No microorganisms exist
Introduction of normal microbiota into an
unusual site in the body
Opportunistic pathogen
Resident
Cluster of Differentiation
To identify specific structures on a cell
NO
Sites where pathogens are maintained as
a source of infection
Animal
1) Human carrier
2) Non-living reservoir
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60. What are zoonoses?
61. What are 3 ways you can acquire
zoonoses?
62. Are humans usually dead-end hosts to
zoonotic pathogens?
63. What is a human carrier?
64. ______ is one type of non-living
reservoir.
65. What are 2 types of non-living
reservoirs?
66. What 2 natural human secretions can
cause contamination in a non-living
reservoir?
67. What is contamination?
68. What is infection?
69. What is portal of entry?
70. What is one major portal of entry that
is found on the external part of the body?
71. What is one major portal of entry that
relates to the nose?
72. What is one major portal of entry that
relates to a fetus?
73. What is one major portal of entry?
74. Portals of Entry
75. Describe how skin is a portal of entry
Diseases that naturally spread from an
animal host to humans
1) Direct contact with an animal or
it’s waste
2) Eating animals
3) Bloodsucking arthropods
YES
An infected individual who is
asymptomatic but infective to others
Soil
1) Food
2) Water
1) Urine
2) Feces
The presence of microbes in or on the
body
When a microorganism evades the
body’s external defenses, multiplies, and
becomes established in the body
Sites through which pathogen’s enter the
body
Skin
Mucous membranes
Placenta
Parenteral route
Skin, mucous membranes, placenta,
parenteral route
-Outer layer of dead skin cells acts as a
barrier to pathogens
-Some pathogens can enter through
openings or cuts
-Others enter by burrowing into or
digesting outer layers of skin
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7 Epidemiology
76. Describe how mucous membranes
becomes a portal of entry
77. Describe how the placenta is a portal
of entry
78. Describe how the parental route is a
portal of entry
79. Role of adhesion in infection
80. What is the invasion of the host by a
pathogen?
81. What is the result if invading
pathogens alter normal body functions?
82. The incidence or prevalence of disease
is also known as what?
83. The chance of death occurring from a
disease
-Line the body cavities that are open to
the environment
-Provide a moist, warm environment
hospitable to pathogens
-Respiratory tract is the most common
site of entry
-Entry is through the nose, mouth, or
eyes
-GI tract may be route of entry, must
survive the acidic pH of the stomach
-Typically forms effective barrier to
pathogens
-Pathogens may cross the placenta and
infect the fetus which can cause
spontaneous abortion, birth defects,
premature birth
-Not a true portal of entry
-Means by which the portal of entry can
be circumvented
-Pathogens deposited directly into tissues
beneath the skin or mucous membranes
-Process by which microorganisms attach
themselves to cells
-Required to successfully establish
colonies within the host
-Attachment proteins help in adhesion
-Found on viruses and many bacteria
-Viral or bacterial ligands bind host cell
receptors
-Interaction can determine host cell
specificity
-Changing/blocking a ligand or its
receptor can prevent infection
-Inability to make attachment proteins or
adhesins renders microorganisms
avirulent
-Some bacterial pathogens attach to each
other to form a biofilm
infection
disease
Morbidity
Mortality rate
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7 Epidemiology
84. What are the three manifestations of
disease?
85. Which subjective characteristics are
only felt by the patient?
86. Which objective measures are
observed by others?
87. What are clinical manifestations which
contain both signs and symptoms which
characterize a disease or abnormal
condition?
88. What type of infections lack
symptoms but still may have signs of
infection?
89. Cause of disease is also known as
what?
90. What is the Germ Theory of disease?
91. Who developed a set of postulates that
one must satisfy in order to prove a
particular pathogen caused by a particular
disease?
92. Exceptions to Koch’s postulate
93. Difficulties in satisfying Koch’s
postulate
94. What are the factors of infectious
agents?
95. What does pathogenicity mean?
96. What does virulence mean?
97. What are some examples of virulence
factors?
98. Extracellular enzymes are secreted by
what?
99. Extracellular enzymes do what to the
structural chemicals in the body?
100. Extracellular enzymes help
pathogens to do what?
Symptoms, Signs, and Syndromes
Symptoms
Signs
Syndromes
Asymtomatic or subclinical
Etiology
Disease caused by infections of
pathogenic microorganisms
Robert Koch
Some pathogens can’t be cultured in the
laboratory
Diseases caused by a combination of
pathogens and other cofactors
Ethical considerations prevent applying
Koch’s postulates to pathogens that
require a human host
Diseases can be caused by more than one
pathogen
Pathogenicity and Virulence
The ability of a microorganism to cause
disease
How easy it is for a particular
microorganism to cause disease
Adhesion factors
Biofilms
Extracellular enzymes
Toxins, Antiphagocytic factors
Pathogens
Dissolve
Maintain infection, invade, and avoid
body defenses.
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7 Epidemiology
101. Another Virulence factor of
Infectious Agents
102. Toxins are:
103. There are two types of toxins.
104. A virulence Factor of Infectious
Agents
105. Factors prevent phagocytosis by the
host’s phagocytic cells
106. Two types of Antiphagocytic factors
Toxin
-
Chemicals that harm tissues or
trigger host immune responses that
cause damage
- Toxemia refers to toxins in the
bloodstream that are carried beyond
the site of infection
Exotoxins
Endotoxins
Antiphagocytic factors
Antiphagocytic factor
Bacterial capsule
Antiphagocytic chemicals
107. Bacterial capsule
Composed of chemicals not recognized
as foreign
Slippery, difficult for phagocytes to
engulf bacteria
108. Antiphagocytic chemicals
Prevent fusion of lysosome and
phagocytic vesicles
Leukocidins directly destry phagocytic
white blood cells
109. What are the five stages of Infectious -Incubation period
Disease
-Prodromal period
-illness
-decline-convalescence
110. The disease process occurs
Following infection
111. What are the stages of infectious
1. Incubation period
disease?
2. Prodromal period
3. Illness
4. Decline
5. Convalescence
112. Are there any signs and symptoms
No
during the Incubation period?
113. How do Pathogens leave hosts?
Pathogens often leave hosts in
materials the body secretes or excretes
114. Where is transmission from
Infectious Disease?
115. What are the three groups of
transmission?
Transmission is from a reservoir or a
portal of exit to another host’s portal of
entry
1. Contact transmission
2. Vehicle transmission
3. Vector transmission
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7 Epidemiology
116. What are FIVE ways to classify
Infectious Diseases?
117. What are SIX terms used to classify
Infectious Disease?
118. Definition of Epidemiology
119. Define contamination
120. Definition of Infection
121. Definition of Disease
122. What is FREQUENCY OF
DISEASE?
123. Number of new cases of a disease in
a given area during a given period of
time.
124. Number of total cases of a disease in
a given area during a given period of
time.
125. What is Descriptive epidemiology?
126. What is Analytical epidemiology?
The Body System they affect
Taxonomic Categories
Their longevity and severity
How they are spread to their host
The effects they have on populations and
not individuals
Acute Disease
Chronic Disease
Subacute Disease
Latent Disease
Communicable
Contagious
The study of where and when diseases
occur, and how they are transmitted.
Presence of microbes
When organism evades body’s external
defenses, multiplies, and becomes
established in the body
Symptomatic consequence of infection
Track occurrence of diseases using
two measures
Occurrence also evaluated in terms
of frequency and geographic
distribution
Incidence
Prevalence
 Careful tabulation of data
concerning a disease
 Record location and time of the
cases of disease
 Collect patient information
 Try to identify the index case (or
first case) of the disease
1. Seeks to determine the probable
cause (etiology), mode of
transmission, and methods of
prevention
2. Useful in situations when Koch’s
postulates can’t be applied
3. Often retrospective
4. Investigation occurs after an
outbreak has occurred
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127. Experimental epidemiology
128. What are Nosocomial infections?
129. What are types of Nosocomial
infections?
130. The interplay of factors that result in
nosocomial infections
131. How do we control Nosocomial
infections?
132. What does The United States Public
Health Service and World Health
Organization (WHO) do?
133. How do public health agencies work
to limit disease transmission?
134. What is antisepsis?
135. What is one example of an
antiseptic?
136. What is aseptic?
137. What do the suffixes –cide and –
cidal mean?
138. What is degerming?
139. What is disinfection?
122. What is pasteurization?
123. What is sanitation?
124. What do the suffixes –stasis and –
static mean?
 Involves testing a hypothesis
concerning the cause of a disease
 Application of Koch’s postulates
is experimental epidemiology
Infections which are acquired in a
hospital (or doctor’s office)
 Exogenous
 Endogenous
 Iatrogenic (caused by a doctor or
nurse)
Presence of microorganisms in hospital
environment, immunocompromised
patients, transmission of pathogens
between and among patients = causes
NOSOCOMIAL INFECTION
- Precautions designed to reduce factors
that result in disease
- Hand washing is the most effective way
to reduce nosocomial infections
Agencies at the local, state, national, and
global level share information
concerning disease
- Monitor water and food safety
- Public health agencies campaign to
educate the public on healthful choices to
limit disease
Reduction in the number of
microorganisms and viruses, particularly
on living tissue
Alcohol
Refers to an environment or procedure
free of pathogenic contaminants
Destruction of a type of microbe
Removal of microbes by mechanical
means
Destruction of most microorganisms and
viruses on nonliving tissue
Use of heat to destroy pathogens and
reduce the number of spoilage
microorganisms in foods and beverages
Removal of pathogens from objects to
meet public health standards
Inhibition, but not complete destruction,
of a type of microbe
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7 Epidemiology
125. What is sterilization?
Destruction of all microorganisms or
viruses in or on an object
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