Chapter 10

Question 1

Dysbiosis

Answer 1

microbiota disruption

Question 2

What could be said about Normal Microbiota and Opportunistic Pathogens

Answer 2

Though some microbes can be normal microbiota for on species, it could be a harmful pathogen for another

Question 3

Pathogenicity

Answer 3

ability of a microbe to cause disease

Question 4

Virulence

Answer 4

The degree or extent of disease that a pathogen causes

Question 5

Virulence: Low v High

Answer 5

low are easy to treat, high is difficult to treat

Question 6

Virulence factors

Answer 6

ways pathogens overcome our defenses

Question 7

What does it take for a pathogen to persist

Answer 7

Must endure over time
Must find a balance b/n breaking down defenses and living within a host

Question 8

How are agents that kill a host quick like?

Answer 8

Cause high-mortality outbreaks
Are short in duration
Are geographically isolated

Question 9

What happens when pathogen is grown in a culture?

Answer 9

Agent becomes attenuated, weakened, could be used as a vaccine

Question 10

Infectious dose-50

Answer 10

Number of cells or virions needed to establish an infection in 50% of exposed hosts

Question 11

Low v High ID-50

Answer 11

High: takes a lot more organisms to start infection
Low: only takes a few organisms to start an infection

Question 12

Lethal dose-50

Answer 12

amount of toxin needed to kill 50% of affected hosts that aren’t treated

Question 13

High v Low LD-50

Answer 13

High: Takes a lot of toxin to kill host
Low: Takes little toxin to kill host

Question 14

Toxins

Answer 14

molecules that generate a range of adverse host effects such as tissue damage and suppressed immune response

Question 15

Toxigenic

Answer 15

Microbes that make toxins

Question 16

Toxemia

Answer 16

toxins in the bloodstream

Question 17

Classes of toxins

Answer 17

Endotoxin
Exotoxin

Question 18

Endotoxin

Answer 18

Specific to gram “-“ bacteria, due to outer membrane having LPS, released into blood stream when bacteria dies

Question 19

Exotoxin

Answer 19

Toxic, soluble proteins that can affect a wide range of cells and can be gram “+” or “-“

Question 20

Exotoxin types

Answer 20

Neurotoxins – affect the nervous system
Enterotoxins – target the GI tract
Hepatotoxins – affect the liver
Nephrotoxins – damage the kidneys

Question 21

Type 1 Exotoxins

Answer 21

Membrane-acting extracellular toxins that bind to target via receptors on the surface

Question 22

Type 2 Exotoxins

Answer 22

Membrane-damaging toxins that disrupt the host cell plasma membrane causing lysis

Question 23

Type 3 Exotoxins

Answer 23

Intracellular toxins that bind to a receptor and enter the cell

Question 24

What are the 5 steps to infection?

Answer 24

Enter the host
Adhere to host tissues
Invade tissues and obtain nutrients
Replicate while warding off immune defenses
Transmit to a new host

Question 25

Portal of entry

Answer 25

any site that a pathogen uses to enter the host

Question 26

Adhesins

Answer 26

virulence factors used to stick to host cells in a specific or nonspecific manner

Question 27

Invasins

Answer 27

Allow pathogens to invade host tissues

Question 28

Cytopathic effects

Answer 28

Cytocidal: kills cells Noncytocidal: non-lethal warfare on cells

Question 29

Latency

Answer 29

ability to exist with stealth inside host

Question 30

Antigenic masking

Answer 30

When in host, pathogen conceals antigenic features, by coating itself with host molecules

Question 31

Antigenic masking: Mimicry

Answer 31

Emulating host molecules, capsules resembling host carbohydrates

Question 32

Antigenic masking: Variation

Answer 32

Continuously altering its surface molecules, thus preventing immune response

Question 33

How do cells avoid phagocytosis

Answer 33

Bursting from of phagosome Blocking fusion of phagosome with lysosome Neutralize enzymes of phagocytes Use chemical warfare against phagocytes

Question 34

Portal of Exit

Answer 34

like portal of entry, but for leaving. Isn't usually the same as entry portal, but can be

Question 35

Symptoms when a pathogen transmits to others

Answer 35

Itchiness Sneezing Coughing Diarrhea

Question 36

Biosafety levels

Answer 36

Dictates the behavior of the job, since healthcare workers in come in contact with pathogens on a near daily basis. However, not all pathogens have the same level of harm

Question 37

BSL criteria

Answer 37

Level infectivity Mortality rates/extent of disease Mode of transmission Availability of preventions or treatments

Question 38

BSL 1-4

Answer 38

1.Rarely cause disease in healthy people 2.Infectious agents associated with human infection; not airborne 3. Serious or lethal human diseases, Many have airborne transmission 4. Dangerous and “exotic” pathogens, Tend to be lethal in humans

Question 39

Standard/universal precautions

Answer 39

Limiting bloodborne pathogens All patients are treated like they are that Handling precautions

Question 40

Transmission precaustion

Answer 40

1-contact disease transmission: Minimize transmission of infectious agents spread by fomites and healthcare workers 2-droplet disease transmission: Procedural mask when in the patient’s room Limit patient transport 3-airborne disease transmission: Airborne infection isolation room (AIIR) Specialized pressure systems