Exam 1 Flashcards
1
Q
what is rational antimicrobial use?
A
the use of antimicrobial agents aimed at maximizing therapeutic efficacy while minimizing risks associated with development of resistance
2
Q
what are the 3 ways to optimize dosage regimens?
A
- shoot high
- shoot regular
- shoot fast
3
Q
what does it mean to shoot high
A
use the highest possible dose, to enhance therapeutic efficacy and prevent resistant mutants
4
Q
what does it mean to shoot regular?
A
administer the drug at regular intervals
5
Q
what does it mean to shoot fast?
A
treat the earliest and for the shortest time possible
6
Q
what is antimicrobial stewardship?
A
coordinated interventions designed to improve and measure the appropriate use of antimicrobials by promoting the selection of the optimal antimicrobial drug regimen, dose, duration of therapy, and route of administration.
7
Q
the discipline concerned with preventing nosocomial or healthcare-associated infection
A
Hospital infection control
8
Q
what are 3 management tools every veterinary clinic should posses?
A
- formal infection control program
- written manual
- infection control practitioner
9
Q
how long should soap be in contact with your hand before rinsing?
A
minimum 20s
10
Q
what does AST stand for
A
antimicrobial susceptibility testing
11
Q
why do we need AST
A
- guidance to antimicrobial therapy
- surveillance of antimicrobial resistance
- antimicrobial drug discovery
12
Q
what are the 2 methods for AST
A
- Dilution method
2. agar diffusion method
13
Q
what are thession E-test 2 dillution methods for AST
A
- broth dilution tests (quantitative)
2. agar dilution tests (quantitative)
14
Q
what are the 2 agar diffusion methods of AST
A
- disk/tablet diffusion test
2. gradient difffu
15
Q
Explain what MIC is
A
Minimum inhibitory concentration
the lowest concentration that inhibits complete
16
Q
Explain what MBC is
A
Minimum bactericidal concentration.
the lowest concentration that kills the test strain
17
Q
when is agar dilution primarily used
A
research purposes like when many strains have to be tested with one drug
18
Q
What is a breakpoint?
A
a drug specific value to interpret the results of susceptibility testing and determine if an antibacterial is potentiall useful in the treatment of bacterial infection
19
Q
what is the susceptible strain in AST
A
the strain is inhibited at blood concentrations achieved by standard dosage of the drug
20
Q
what is the intermediate strain in AST
A
clinical efficacy is possible if the strain infects body sites where the drug concentrates or if the dosage can be increased compared to standard dosage
21
Q
what is the resistant strain in AST
A
the strain is not inhibited at blood concentrations achieved by standard dosage of the drug
22
Q
what are the 3 most frequent bacterial contaminants in AST
A
coagulase-negative staphyilococci, bacillus spp., Enterococci
23
Q
why are surrogate antimicrobials used in AST
A
to predict susceptibility to other drugs belonging to the same class.
24
Q
what are the two drugs used for detection of MRSA/MRSP
A
oxacillin and cefoxitin
25
what is the MRSA expert rule?
strains resistant to oxacillin/cefoxitin should be regarded as resistant to all B-lactams irrespective of their susceptibility to penicillins and cephalosporins in the report
26
why are oxacillin and cefoxitin used for the detection of MRSA/MRSP
because the methicillin resistance gene mecA is poorly expressed in laboratory media
27
ESBLs confer resistance to third generation cephalosporins shuch as ______, ______, and ______
cefpodoxime, cefotaxime, ceftazidime
28
name the 2 superbugs that infect both hospitals and the cummunity
Meticillin-resistant S. aureus (MRSA) and ESBL-producing E.coli
29
What is intrinsic resistance
resistance due to structural or functional traits present in all members of a given bacterial species or group
30
name the two ways bacteria acquire resistance?
mutation and horizontal gene transfer
31
what are the 3 mechanisms in which horizontal gene transfer occures in bacteria
1. transformation (uptake of free DNA)
2. transduction (transfer mediated by phage delivery)
3. conjugation (transfer cell to cell contact)
32
what is the resistant gene in MRSA
mecA
33
what is the penicillin binding protein of mecA
PBP2A
34
which type of antibiotics does MRSA have a low affinity for
B-lactams (penicilins and cephalosporins)
35
most common strain of MRSA in companion animals
CC22
36
Most common strain of MRSA in horses and pigs
CC398
37
Most common strain of MRSAQ in just horse=
cc8
38
Most common strain of MRSA in just swine
CC9
39
what is MRSP
Methicillin Resistant Staphylococcus Pseudintermedius; it is a S. Pseudintermedius that has acquired mecA
40
what is ESBL
Extended Spectrum Beta Lactamase; it is an enzyme hydrolizing/inactivating most B-lactams produced by Gram Negative Bacteria
41
what are teh 3 main classes of ESBLs
CTX-M
SHV
TEM
42
what is the most common type of ESBL in animals
CTX-M-1
43
Name a common false ESBL found in europe
CMY-2
44
what is virology
the study of viruses and viral diseases
45
what is a virologist
someone who studies viruses
46
T/F viruses are living entities
F
47
Viruses contain a _____ Genome surrounded by a _______ coat
```
Nucleic acid (DNA or RNA);
Proteiin coat (Capsid)
```
48
T/F Viruses contain mitochondria but do not have golgi apparatuses
F, no organelles
49
Where do viruses get their proteins and energy
host cell, cannot make on own
50
T/F viruses are facultative intracellular parasites
F obligate intracellular parasites
51
T/F viruses do not have the genetic capability to multiply by Division
T
52
What is a capsid
the protein shell of a virus that envelopes the viral nucleic acid/genome
53
what is the capsid of a virus made of
capsomeres held together by non-covalent bonds
54
what is a nucleocapsid?
capsid+DNA/RNA
55
some viruses have an additional layer that covers the capsid known as
The Lipid Envelope
56
what is the lipid envelope made of?
lipid bilayer from host cell
57
what are present on the surface of the envelope that often have spike like appearance
Glycoproteins
58
Term for virus that have only a protein capsid enclosing nucleic acid, no lipid envelope present:
Naked Viruses/ Non-Enclosed Viruses
59
term for viruses that have an additional lipid layer enclosing the protein capsid enclosing Nucleic Acid
Enveloped Viruses
60
what is pleomorphism
the ability of some viruses to alter their shape and size
61
what are the 6 stages of virus replication
1. Attachment
2. penetration
3. uncoating
4. synthesis of viral nucleic acid and protein
5. Assembly and maturation
6. release in large numbers
62
what are the 4 outcomes of the host cell after viral infection
1. cell death
2. No apparent change
3. transformation of cell to malignant cell
4. fusion of cells
63
what are the 3 types of cell death
1. lysis
2. alteration cell membrane
3. apoptosis
64
what is the name of the body charged with the task of developing, refining, and maintaining a universal virus taxonomy
The international committee on taxonomy of viruses (ICTV)
65
what are the 7 types of viral transmission
1. direct contact
2. indirect contact
3. common vehicle
4. Airborne Transmission
5. Vector borne transmission
6. zoonotic transmission
7. vertical transmission
66
type of viral transmission where animal becomes infected by physical contact with host
direct contact transmission
67
tye of viral transmission where animal becomes infected by fomites
indirect contact transmission
68
type of viral transmission where animal becomes infected by eating or drinking contaminated food
common-Vehicle transmission
69
type of viral transmission where infection if transferred from mother to embryo, fetus, or newborn before, during, or after parturition
vertical transmission
70
3 ways we can grossly diagnose viral infections
1. clinical sighns
2. necropsy
3. histopathology
71
2 ways we can diagnose viral infections by cultivation
1. isolation of viruses in cells/tissue culture
| 2. inoculation in eggs
72
the detection of viral antigen or host antibody against virus is known as
serology
73
what does ELISA stand for
Enzyme linked immunosorbent assay
74
name the 2 serologic techniques use dto detect a virus
1. fluorescent antibody staininog
| 2. immunohistochemical staining
75
what technique do we use to detect the nucleic acids of viruses
PCR
76
what are the 3 ways we can treat viruses
1. antiviral drugs
2. immune system stimulation
3. synthesize antibodies or administration of natural antiserum
77
_______ are a class of proteins that have antiviral effects and modulate functions of the immune system
interferons
78
how do we prevent viral infections
1. vaccinate
2. proper hygiene/sanitation
3. eliminate arthropod vectors
4. quarantine and culling
79
what are the 3 types of vaccines we use to vaccinate against viruses
1. live-attenuated viruses vaccines
2. Non-Replicating virus vaccines
3. vaccines produced by recombinant DNA and related technologies
80
Type of management system where animal houses are cleaned between batches of animals
all in, all out
81
Name one type of biological control used to eliminate viruses
predatory fish
82
name one type of chemical control used to eliminate vioruses
use of insecticides
83
what is pathogenicity
the ability of a virus to cause disease in a host
84
what is a pathogen
virus that causes disease
85
what is pathogenesis
the mechanism of development of a disease
86
what is virulence?
relative measure of the degree of pathogenicity of the infecting virus
87
what is avirulent?
not virulent/ not harmful to host
88
T/F virulence is an absolute property
F, Is not absolute
89
5 Virulence factors related to virus
1. genetic variation of virus
2. route of entry of virus in host
3. affinity of virus to host organs
4. dose of infection
immuno evasion
90
4 Virulence Factors related to host
1. host species
2. host immunity
3. host physiological factors
4. fever
91
2 virulence factors related to the outcome of tug of war
environment and dual infections
92
how do we measure virulence
lethal dose 50 (LD50)
93
what is LD50
the dose of the virus required to cause deathin 50% of animals
94
Name some routs of entry for viruses to enter animal
1. cut in skin
2. Mucous membrane
3. GI tract
4. Respiratory tract
95
how does a virus spread once inside the host
1. local spread of virus on epithelial surface
2. from local infection of epithelia to subepithelial invasion and lymphatic spread
3. to blood stream and then spread via blood
96
what does viremia mean
presence of virus in blood
97
what is the difference between primary and secondary viremia?
Primary= initial entry of virus into blood
Secondary= virus has replicated in organs and once more entered into circulation
98
what is a disseminated infection?
infection spreads beyond the primary site of infection
99
what is systemic infection
if a number of organs or tissues are infected
100
what are the 3 ways viruses are spread through nerves
1. through peripheral nerves
2. through receptor neurons in the nasal epithelium
3. BBB and infect CNS
101
what is a neurotropic virus
viruses that can infect neural cells. infection may occur by neural or hematogenous sporead
102
what is a neuroinvasive virus
viruses that enter the CNS after infection
103
what is a neurovirulent virus
viruses that cause disease of nervous tissue, manifested by neurological symptoms and often death
104
what is tropism
the specificity of a virus for a particular host tissue
105
what are pantropic viruses
can replicate in more than one host organ
106
what are the 5 ways that viruses interact with the host cell
1. inhibition of host cell nucleic acid synthesis
2. inhibition fo host cell RNA synthesis
3. inhibition of host cell protein synthesis
4. cytopathic effects of toxic viral proteins
5. interference with cellular membrane function
107
what is an oncoviruse
a virus that can cause cancer
108
type of infection usually characterized by intensive shedding over a short period of time
acute infection
109
type of infection characterized by shedding at lower titers over months or years
persistent infections
110
what is a vesicle
fluid filled sac
111
The name for benign skin growths that appear when a virus infects the top layer of the skin
Warts
112
what is erythema
reddening of the skin
113
a viral infection of the respiratory tract causes _____
inflammation, obstruction of air passages, and hypoxia and respiratory distress
114
when the CNS is infected with a virus what 4 side effects are typically seen?
1. lytic infections of neurons
(destruction)
2. neuronal necrosis (death of body tissue)
3. neuronophagia (killing of neuronal cells by phagocytic cells)
4. perivascular cuffing (inflammatory cells around blood vessels in CNS)
115
Viral infections of the hemopoietic system cause what 2 things
1. damage to endothelium (hemorrhages)
| 2. clots form throughout body
116
viral infection of the fetus are known as ______
Teratogenic viruses
117
how do prokaryotic cell replicate
binary fission
118
how do eukaryotic cells replicate
mitosis
119
How do you name Bacteria?
Genus and species
Genus: capitialized and italicized
species: italicized
subspecies: italicized
Serovar: not italicized, Capitalized
120
what is included in the nucleoide of bacteria?
DNA, RNA, NAPs, DNA gyrase, topoisomerase 1
121
T/F the plasmid of a bacterial cell is not part of the nucleoid
T
122
what is the importance of the plasmid
contains genes for resistance of virulence factors
123
how do bacterial plasmids transmit their genes
conjugation
124
what is the importance of the bacterial envelope
provides protection, energy, and adhesion
125
what is the importance of the bacterial capsule
helps bacteria evade immune system, tolerance to drugs
126
Gram Negative bacteria will stain ______ whereas gram positive bacteria will stain ______.
Pink; Purple
127
what is the LPS present in the gram negative cell wall
endotoxin
128
T/F gram positive bacteria contain lipoteichoic acid and a thick peptidoglycan layer
T
129
what does monotrichous mean?
singular flagella
130
what is the term for multiple polarized flagella
lephotrichous
131
what is the term for multiple flagella spread around the entire organism?
peritrichous
132
what is the term fro two flagella polorized at opposite ends
amphitrichous
133
what is the difference between antimicrobial and antibiotic?
antimicrobial is any substance that kills or inhibits the growth of microorganisms
antibiotics- any substance produced by a microorganism that kills or inhibits the growth of other microorganisms
134
T/F all antimicrobials are antibiotics, but all antibiotics are antimicrobials
F, all antibiotics are antimicrobials but not all antimicrobials are antibiotics
135
what are 3 ways we can classify antimicrobials
1. mode of action
2. effect on bacteria
3. spectrum
136
which category of drugs are good against gram + cocci? Bad?
Penicillin
Metronidazole
137
Which category of drugs are good against gram - Rods? Bad?
G
1. amoxicillin + CA
2. Cephalosporins
3. Sulfonamides
4. Aminoglycosides
5. Fluroquinolones
B
1. Metronidazole
2. Penicillin
3. Macrolides
138
which category of drugs are good against Staphylococci? Bad?
G
1. Amoxicillin + CA
2. Cephalosporins
3. sulfonamides
4. aminoglycosides
5. Fluroquinolones
B
1. Metronidazole
2. penicillin
139
which category of drugs are good against Anaerobes? Bad?
G
1. Metronidazole
2. Penicillin
B
Aminoglycosides
140
T/F there are more pathogenic bacteria than non-pathogenic bacteria
F
141
what is the MoA of B-lactams
inhibit cell wall synthesis
142
what are the 5 ways antibacterial agents are classified
1. chemical structure
2. origin
3. effect on bacteria
4. spectrum of activity
5. mode of action
143
Name the 3 types of B-lactams discussed
1. penicilins
2. carbapenems
3. Cephalosporins
144
Bactericidal drugs _____ whereas bacteriostatc drugs ________
kill; inhibit growth
145
what is co-resistance
refers to the co-existance of multiple genes or mutations encoding resistance to different drugs within the same strain or genetic element
146
what is co-selection
the selection of multiple resistance genes when one of these genes is selected
147
what is commensalism
good for one, no effect on other
148
two types of pathogenic organisms
1. Facultative pathogenic
| 2. obligate pathogenic
