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T1 - Phase 2 - Systems Modules (I) > Infectious DIsease - Viral Basics > Flashcards

Infectious DIsease - Viral Basics Flashcards

1
Q

A virus is an infectious, ________ intracellular parasite comprising genetic material (DNA or RNA), surrounded by a ________ coat and sometimes a ________.

A

A virus is an infectious, obligate intracellular parasite comprising genetic material (DNA or RNA), surrounded by a protein coat and sometimes a membrane.

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2
Q

The basic building blocks of any virus are a genome, a _________ (protein coat), and possibly an _________ (membrane).

A

The basic building blocks of any virus are a genome, a capsid, (protein coat) and possibly an envelope (membrane).

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3
Q

True/False.

Different virusal species can contain a genome made of DNA, RNA, or a mix of both.

A

False.

Different virusal species can contain a genome made of either DNA or RNA.

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4
Q

Is there much variation in how viral genomes are organized?

A

Yes

(can be linear, circular, segmented; positive-sense, negative-sense; single-stranded, double-stranded; etc.)

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5
Q

What part of the viral genome encodes for protein synthesis machinery (tRNA, rRNA, eIFs, etc.)?

What part of the viral genome encodes for proteins and that regulate energy production?

What part of the viral genome encodes for biosynthesis of membranes?

A

None;

none;

none

(the above categories do not exist in viral genomes)

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6
Q

Describe a few of the basic structures that viral capsids can form.

A
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7
Q

True/False.

Forming the protein coat (capsid) that surrounds the viral genome is a fairly complex process that is probably one of the most intricate and energy-dependent processes controlled by the virus.

A

False.

The capsid is often made of subunit monomers that can self-assemble into the larger whole with no enzymatic or energetic requirements.

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8
Q

Viral capsids must be ______stable so that they can survive the external environment but will easily come apart inside host cells.

A

Viral capsids must be metastable so that they can survive the external environment but will easily come apart inside host cells.

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9
Q

In order to create a metastable viral capsid, what type of bond usually holds the capsid subunits together?

A

Loose, electrostatic interactions

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10
Q

The two most common types of symmetry seen in viral capsids are _________ and _________ symmetry.

What is the term that refers to capsids not following these patterns?

A

The two most common types of symmetry seen in viral capsids are helical and icosahedral symmetry.

Complex

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11
Q

Which viral capsule shape is always enveloped?

A

Helical

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12
Q

What type of virus has the most complex capsid structure?

A

Bacteriophages

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13
Q

A virus surrounded by a bilipid membrane is called a(n) ___________ virus.

A virus not surrounded by a bilipid membrane is called a(n) ___________ virus.

A

A virus surrounded by a bilipid membrane is called an enveloped virus.

A virus not surrounded by a bilipid membrane is called a naked virus.

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14
Q

______________ viruses are released from their host cells via cell lysis.

______________ viruses are released from their host cells via budding (cell survives) or lysis.

A

Naked viruses are released from their host cells via cell lysis.

Enveloped viruses are released from their host cells via budding (cell survives) or lysis.

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15
Q

Enveloped viruses are released from their host cells via ________ or ________.

Naked viruses are released from their host cells via ________.

A

Enveloped viruses are released from their host cells via budding (cell survives) or lysis.

Naked viruses are released from their host cells via cell lysis.

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16
Q

_________ viruses are resistant to heat, acids, detergents, dessication, etc.

_________ viruses are not.

A

Naked viruses are resistant to heat, acids, detergents, dessication, etc. (stabile).

Enveloped viruses are not (labile).

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17
Q

A dessicated _________ (naked / enveloped) virus is still infectious.

A

A dessicated naked virus is still infectious.

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18
Q

Can a naked or an enveloped virus or both survive within the GI tract?

A

Naked only

(stable)

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19
Q

Naked viruses stimulate what immune response?

Enveloped viruses stimulate what immune response?

A

Antibody production;

antibody production, cell-mediated response

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20
Q

What advantages are conferred on an enveloped virus via the presence of its membrane?

A

Some protection from host immune responses, enzymes, and certain chemicals

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21
Q

How are enveloped viruses typically transmitted?

(Labile viruses)

A

Droplets,

secretions

(also, transplants)

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22
Q

How are naked viruses typically transmitted?

(Stabile viruses)

A

Fomites,

dust,

fecal-oral,

droplets

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23
Q

True/False.

Some virusal genomes encode for lipid membranes so the virus can become ‘enveloped.’

A

False.

All viral envelopes are derived from host cell membranes (viruses do not encode membrane production).

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24
Q

Although enveloped viruses form their envelopes from host cell membranes, how does the virus change the membrane?

A

Insertion of glycoproteins

(for host cell attachment, antigenicity, etc.)

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25
Q

Describe how viral glycoproteins allow for viral envelope formation from host cell membranes.

A

Via matrix proteins

(mediators of capsid-glycoprotein interactions)

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26
Q

What determines viral attachment to and specificity for host cells?

A

Surface proteins

(capsid proteins or envelope glycoproteins)

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27
Q

All viruses are in the order ‘-virales.’

The suffix for viral familal classifications is: ‘-_______.’

The suffix for viral genus classifications is: ‘-_______.’

The species are then named more specifically.

(Kingdom –> phylum –> Class –> Order –> Family –> Genus –> Species)

A

All viruses are in the order ‘-virales.’

The suffix for viral familal classifications is: ‘-viridae.’

The suffix for viral genus classifications is: ‘-virus.’

The species are then named more specifically.

(Kingdom –> phylum –> Class –> Order –> Family –> Genus –> Species)

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28
Q

No matter their genome structure, all viruses converge at a need to synthesize _______ to alter host function.

A

No matter their genome structure, all viruses converge at a need to synthesize mRNA to alter host function.

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29
Q

What mnemonic is useful in remembering which viral families are DNA viruses?

A

DNA viruses are HHAPPPPy

Hepadnaviridae

Herpes

Adenoviridae

Poxviridae

Parvoviridae

Papilloma

Polyoma

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30
Q

The mnemonic HHAPPPPy is useful in remembering which viral families are DNA viruses. Name the viruses:

H_________

H_________

A_________

Poxviridae

Parvoviridae

Papilloma

Polyoma

A

Hepadnaviridae

Herpes

Adenoviridae

Poxviridae

Parvoviridae

Papilloma

Polyoma

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31
Q

The mnemonic HHAPPPPy is useful in remembering which viral families are DNA viruses. Name the viruses:

Hepadnaviridae

Herpes

Adenoviridae

P_________

P_________

Papilloma

Polyoma

A

Hepadnaviridae

Herpes

Adenoviridae

Poxviridae

Parvoviridae

Papilloma

Polyoma

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32
Q

The mnemonic HHAPPPPy is useful in remembering which viral families are DNA viruses. Name the viruses:

Hepadnaviridae

Herpes

Adenoviridae

Poxviridae

Parvoviridae

P_______

P_______

A

Hepadnaviridae

Herpes

Adenoviridae

Poxviridae

Parvoviridae

Papilloma

Polyoma

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33
Q

All DNA viruses are ________-stranded, except for the _________ family.

A

All DNA viruses are double-stranded, except for the Parvoviridae family.

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34
Q

All DNA viruses are ________ (shape), except for the _________ family.

A

All DNA viruses are icosahedral, except for the Poxviridae family.

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35
Q

All RNA viruses except for the _________ family are __RNA.

A

All RNA viruses except for the Reoviridae family (dsRNA) are ssRNA.

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36
Q

Most viruses only have one copy of their genome.

What type of virus has two?

A

Retroviruses

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37
Q

All viruses must produce ______ to be translated by the host ribosomes.

A

All viruses must produce mRNA to be translated by the host ribosomes.

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38
Q

What are the phases of viral growth as represented on a graph showing infectious virions per cell (Y-axis) and time (X-axis)?

A
  1. Eclipse period
  2. Exponential growth period
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39
Q

The ‘eclipse period’ of viral growth for a certain cell is the time after ____________ in which no virions can be found in the cell due to ___________ (release) of the viral genome.

How long does this process typically take?

What is the next phase?

A

The ‘eclipse period’ of viral growth for a certain cell is the time after infection in which no virions can be found in the cell due to uncoating (release) of the viral genome.

1 - 20 hours;

the exponential period

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40
Q

List the major steps of the viral lifecycle:

  1. _____________
  2. _____________
  3. Uncoating
  4. Synthesis
  5. Assembly
  6. Release
A

List the major steps of the viral lifecycle:

  1. Adsorption (adhesion to cell exterior)
  2. Penetration (entry into cell)
  3. Uncoating
  4. Synthesis
  5. Assembly
  6. Release
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41
Q

List the major steps of the viral lifecycle:

  1. Adsorption
  2. Penetration
  3. ___________
  4. ___________
  5. Assembly
  6. Release
A

List the major steps of the viral lifecycle:

  1. Adsorption
  2. Penetration
  3. Uncoating
  4. Synthesis
  5. Assembly
  6. Release
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42
Q

List the major steps of the viral lifecycle:

  1. Adsorption
  2. Penetration
  3. Uncoating
  4. Synthesis
  5. ___________
  6. ___________
A

List the major steps of the viral lifecycle:

  1. Adsorption
  2. Penetration
  3. Uncoating
  4. Synthesis
  5. Assembly
  6. Release
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43
Q

True/False.

During the eclipse period of the viral lifecycle, only viral fragments are present inside the host cell.

A

True.

Uncoating of the genome has occurred and no complete virions are detectable until new virions have been synthesized and assembled.

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44
Q

A __________ cell has the receptor that a specific virus binds. A __________ cell does not.

A permissive cell may be either of the above, and this cell does have the capacity to replicate the virus should it enter.

A

A susceptible cell has the receptor that a specific virus binds. A resistant cell does not.

A permissive cell may be either of the above, and this cell does have the capacity to replicate the virus should it enter.

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45
Q

A susceptible cell has the receptor that a specific virus binds. A resistant cell does not.

A __________ cell may be either of the above, and this cell _____ (does / does not) have the capacity to replicate the virus should it enter.

A

A susceptible cell has the receptor that a specific virus binds. A resistant cell does not.

A permissive cell may be either of the above, and this cell does have the capacity to replicate the virus should it enter.

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46
Q

True/False.

A cell must be either susceptible (viral receptor present) or permissive (can replicate the virus) in order to successfully take up and replicate a specific virus.

A

False.

A cell must be both susceptible (viral receptor present) and permissive (can replicate the virus) in order to successfully take up and replicate a specific virus.

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47
Q

Viral adsorption describes viral __________ coming into contact with cell __________.

A

Viral adsorption describes viral proteins coming into contact with cell surface proteins.

(E.g. HIV surface proteins interacting with TH cell CD4 and CXCR4)

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48
Q

How do naked viruses typically penetrate the cell?

And enveloped viruses?

A

Direct penetration OR endocytosis;

membrane fusion OR endocytosis

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49
Q

What does it mean that viruses in the Hepadnaviridae family have ‘gapped’ DNA?

A

Their genome is a mix of single- and double-stranded DNA

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50
Q

All viral ssDNA or gapped DNA must be converted to _______ in the host nucleus before it can be transcribed to mRNA.

A

All viral ssDNA or gapped DNA must be converted to dsDNA in the host nucleus before it can be transcribed to mRNA.

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51
Q

Ribsome-ready mRNA from a virus is termed ________-sense, meaning it is ready for immediate translation.

A

Ribsome-ready mRNA from a virus is termed positive-sense, meaning it is ready for immediate translation.

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52
Q

Viral RNA and DNA __________ of (+) strands are (-) strands.

A

Viral RNA and DNA complements of (+) strands are (-) strands.

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53
Q

True/False.

Positive-sense RNA are ready for translation.

A

Not necessarily!

Positive-sense mRNA are ready for translation, but some positive sense RNA may need adjustment first.

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54
Q

Cells do not make _____-dependent RNA polymerase, but viral genomes do.

A

Cells do not make RNA-dependent RNA polymerase (RdRp), but viral genomes do.

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55
Q

(I) If viral dsDNA enters a host cell, what happens next?

(1st of 7 options in the Baltimore system)

A

(I) Immediate transcription to mRNA

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56
Q

(II) If viral positive-sense ssDNA enters a host cell, what happens next?

(2nd of 7 options in the Baltimore system)

A

(II) It is turned into dsDNA; then, transcribed to mRNA

57
Q

(III) If viral dsRNA enters a host cell, what happens next?

(3rd of 7 options in the Baltimore system)

A

(III) Immediate transcription to mRNA

58
Q

(IV & VI) If viral positive-sense ssRNA enters a host cell, what are the two options as to what happens next?

(4th and 6th of 7 options in the Baltimore system)

A

(IV) It is turned into negative-sense ssRNA; then, transcribed to mRNA

(VI) It is turned into negative-sense ssDNA; then, dsDNA; then, transcribed to mRNA

59
Q

(V) If viral negative-sense ssRNA enters a host cell, what happens next?

(5th of 7 options in the Baltimore system)

A

(V) Immediate transcription to mRNA

60
Q

(VII) If viral gapped DNA (a mix of double- and single-strands) enters a host cell, what happens next?

(7th of 7 options in the Baltimore system)

A

(V) Conversion to dsDNA; then, transcription to mRNA

61
Q

What tool(s) do viral genomes encode to produce RNA from RNA templates?

A

RNA-dependent RNA polymerases (RdRp)

62
Q

Many viral proteins synthesized from DNA templates are assembled where in the host cell?

A

The nucleus

63
Q

Where do positive-sense mRNA get their RNA-dependent RNA polymerase?

Where do negative-sense mRNA get their RNA-dependent RNA polymerase?

(NOTE: RdRp is not made by host cells.)

A

They immediately synthesize it (positive-sense = ready to go);

they bring it with them in the viral capsid

64
Q

What type of genetic material do retroviruses carry?

A

Positive-sense ssRNA

65
Q

What three roles does reverse transcriptase perform for retroviruses (positive-sense ssRNA)?

A
  1. ssRNA –> ssDNA
  2. ssDNA –> dsDNA
  3. Degradation of original ssRNA
66
Q

What main enzyme type allows retroviruses to insert their newly synthesized dsDNA into the host genome?

A

Integrases

67
Q

What enzyme is required for viral ssRNA to become ssDNA or for viral ssDNA to become dsDNA?

A

Reverse transcriptase

68
Q

Does viral reverse transcriptase have RNA-dependent RNA polymerase activity or DNA-dependent DNA polymerase activity?

A

Both

69
Q

True/False.

RNA-dependent RNA polymerases and DNA-dependent DNA polymerases are error-prone resulting in high mutation rates.

A

True.

70
Q

Where do viral RNA genomes typically replicate?

A

The cytoplasm

71
Q

Does proof-reading occur during viral RNA or DNA replication?

A

DNA only

(although, poorly done by viral polymerases — error-prone processes)

72
Q

Assembly of capsids from RNA viruses typically happens where in the host cell?

Assembly of capsids from DNA viruses typically happens where in the host cell?

A

Cytoplasm;

nucleus

73
Q

What is a procapsid?

A

An empty capsid that does not yet contain a viral genome

(viruses are either assembled by forming the coat around the genome or inserting the genome after the coat is assembled)

74
Q

How can naked virions induce host cell death to be released?

A

Necrosis

  • Inhibition of protein synthesis
  • Disorganization of cytoskeleton
  • Alteration of membranes (Lysosome leak)

Apoptosis / pyroptosis

75
Q

How long is the replication cycle for the typical virus (from entering the host cell to thousands of new virions leaving the host cell)?

A

8 - 36 hours

76
Q

What is antigenic shift?

A

The combination of multiple viral species to yield a subtype mix of their collective surface proteins

77
Q

What is antigenic drift?

A

Naturally accumulated mutations in a viral species over time

78
Q

What are the two potential phases of the bacteriophage lifecycle?

A
  1. Lysogenic
  2. Lytic
79
Q

__________ bacteriophages use both the lysogenic and lytic phases.

A

Temperate bacteriophages use both the lysogenic and lytic phases.

80
Q

True/False.

Bacteriophages in the lysogenic phase are not replicating at all.

A

False.

They replicate passively as the bacteria undergoes binary fission.

81
Q

True/False.

Lysogenic phages can carry the ability to form certain toxins between bacterial species.

A

True.

82
Q

What is the typical causal factor inducing a phage to leave the lysogenic (dormant) phase and enter the lytic (cell death) phase?

A

Stress

(ROS, toxins, bacterial cell damage, etc.)

83
Q

Are respiratory droplets responsible for direct or indirect viral transmission?

Are aerosols responsible for direct or indirect viral transmission?

A

Direct;

indirect

84
Q

What is the most common route for viral entry into the body?

A

Respiratory tract

(There are ~100,000 virions per square meter of indoor air!)

85
Q

Why are the eyes poor entry points for infectious agents (assuming the eyes are not damaged)?

A

Constant washing by lacrimal glands

+

IgA

+

lysozymes

86
Q

What term describes the specified spectrum of cells, tissues, or hosts that can be infected by a certain virus?

A

Tropism

(e.g. enterotropic viruses infect the gut; neurotropic viruses infect the nervous system; pantropic viruses infect multiple tissues)

(can be cellular tropism, tissue tropism, host tropism)

87
Q

The stages of viral spread:

Localized –>

__________ –>

__________

A

The stages of viral spread:

Localized –>

Disseminated –>

Systemic

88
Q

Name some forms of viral routes of spread throughout the body.

A

Hematogenous, lymphatic, neural,

fetal (delivery, breast-feeding, placental)

89
Q

What term describes virus presence in the bloodstream?

A

Viremia

90
Q

Name three methods by which viruses can cross the blood-brain barrier.

  1. Replication within ___________ cells (inflammatory)
  2. ____________
  3. Via infected ___________ cells that traverse the barrier
A

Name three methods by which viruses can cross the blood-brain barrier.​

  1. Replication within endothelial cells (inflammatory)
  2. Transcytosis
  3. Via infected immune cells that traverse the barrier
91
Q

Name three methods by which viruses can enter the nervous system.

  1. Via infected _________
  2. By infecting _________ cells (inflammatory)
  3. Via traveling up the _______ to the CNS
A

Name three methods by which viruses can enter the nervous system.

  1. Via infected monocytes
  2. By infecting endothelial cells (inflammatory)
  3. Via traveling up the PNS to the CNS
92
Q

Describe how viruses travel up and down neurons.

A
93
Q

What is a neurotropic virus?

A

One that can infect neurons

94
Q

What is a neuroinvasive virus?

A

Can enter the CNS from a peripheral location

95
Q

What is a neurovirulent virus?

A

One that causes disease of nervous tissue

96
Q

Describe the herpes simplex virus in terms of neurovirulence and neuroinvasiveness.

A

Neurovirulence: High

Neuroinvasiveness: Low

(I.e. it will have very severe effects if it makes it to the CNS, but this is rare.)

97
Q

Describe the mumps virus in terms of neurovirulence and neuroinvasiveness.

A

Neurovirulence: Low

Neuroinvasiveness: High

(I.e. it often infects the CNS but has few effects.)

98
Q

Describe the rabies virus in terms of neurovirulence and neuroinvasiveness.

A

Neurovirulence: High

Neuroinvasiveness: High

(I.e. it often spreads from the PNS to the CNS and is usually lethal.)

99
Q

What is the leading cause of congenital infection?

A

CMV

(typically asymptomatic)

100
Q

What is the best way for infectious agents to disrupt the basement membrane?

A

Inflammation

101
Q

Many viruses produce ________ that block interferon production and produce molecules that bind/inhibit ________.

A

Many viruses produce miRNA that block interferon production and produce molecules that bind/inhibit cytokines.

102
Q

True/False.

Many viruses produce miRNA that promote apoptosis.

A

False.

Many viruses produce miRNA that inhibit apoptosis.

103
Q

Many viruses downregulate MHC-I (or block ____ or proteasomal activity, etc.) to avoid ____ cells.

A

Many viruses downregulate MHC-I (or block TAP or proteasomal activity, etc.) to avoid TC cells.

104
Q

What is an inapparent infection?

A

Asymptomatic, subclinical

105
Q

True/False.

Latent infections often come in recurring rounds.

A

True.

106
Q

Describe the terms epidemic, endemic, pandemic, and sporadic.

A
107
Q
A
  1. Ebola virus is more virulent than HPV

(virulences between viruses cannot be compared)

108
Q

How can viral virulence be quantitated?

A
109
Q

Name a few factors that contribute to the amount of virulence a virus has.

A

Relative dose, route of innoculation, age, gender, susceptibility of host, etc.

110
Q

What is active viremia?

A

Viremia produced by active replication

111
Q

Virulence can only be compared among specific viral infections with what relationship to one another?

A

Viral strains within the same species

(cannot be compared among different viruses)

112
Q

How can a virus be attenuated so that it is safe to give in vaccine form?

A

Knock out its severe virulence factors

(e.g. remove the neurovirulence from the polio virus)

113
Q

True/False.

Only bacteria (not viruses) produce viable exotoxins on any scale large enough to cause obvious signs / symptoms.

A

False.

Many viruses cause significant exotoxin production.

114
Q

Can viral virulence factors be found in untranslated regions?

A

Yes

115
Q

_____lytic viruses induce apoptosis, necrosis, or pyroptosis of infected cells.

Many viruses inhibit host _________ and _________ synthesis.

Viruses may produce ___________ which create porous leakage in host cell membranes.

A

Cytolytic viruses induce apoptosis, necrosis, or pyroptosis of infected cells.

Many viruses inhibit host RNA and protein synthesis.

Viruses may produce viroporins which create porous leakage in host cell membranes.

116
Q

Define syncytium.

A

A multinucleated cell that can result from multiple cell fusions of uninuclear cells

117
Q

What viral process is illustrated in this image?

A

Syncytium formation

118
Q

True/False.

Many viruses can induce the body to release inflammatory vasoactive peptides, bradykinins, histamine, etc.

A

True.

119
Q

The cytokine storm is an example of auto-damage caused by the _________ (innate/adaptive) immune system.

A

The cytokine storm is an example of auto-damage caused by the innate immune system.

120
Q

What are some examples of of auto-damage caused by the adaptive immune system in response to viral damage?

A

CD8+-mediated apoptosis;

CD4+ cytokine release

121
Q

Viral poxes and rashes are typically caused by ____ cell activity.

A

Viral poxes and rashes are typically caused by TH1 cell activity.

122
Q

In response to viral infection, what cell type calls in eosinophils and may result in lesions?

A

TH2

123
Q

What cell type may lead to vasculitis and/or glomerulonephritis in response to viral infection?

Is this more likely to happen on a first infection or second infection?

A

B cells;

second: reinfections can lead to antibody-dependent enhancement of viral infections

124
Q

Name some factors affecting host immunocompetence and susceptibility to viral infection.

A

Host genes (SNPs),

age,

malnutrition,

pregnancy

125
Q

What term describes the release of virions from infected individuals (e.g. in the feces, blood, urine, semen, milk, skin lesions, etc.)?

A

Viral shedding

126
Q

What percentage of infectious cases seen by physicians are viral in nature?

A

60%

127
Q

Laboratory testing can be used to do what in relation to viral infection?

A

Diagnostic confirmation;

determination of antiviral therapy;

check patient medication compliance

128
Q

What are some factors to consider in acquiring a viral sample for laboratory testing?

A

Collection site (oral mucosa, GI tract, urine, etc.)

+

timing (stage of disease, viral load, etc.)

+

proper processing of specimen

129
Q

What is the gold standard for clinical lab testing of viral infection?

A

Viral isolation/culturing

(Very very sensitive and specific; doesn’t work for all viruses)

130
Q

Besides viral isolation/culturing, what are two other methods of viral lab testing?

A

Serology;

direct detection methods

131
Q

What do viruses require for laboratory testing?

A

Living cells

132
Q

What are some drawbacks of viral isolation/culturing in the laboratory setting?

A

Doesn’t work for all viruses;

often takes several days

133
Q

How do rapid cell cultures for viruses work?

A

They enhance viral load at cell surfaces for better infection

+

antibody / fluorescent tag added

134
Q

How do viral plaque assays work?

A
135
Q

Name a few laboratory methods of viral antigen identification.

  • _______ forming assay
  • __________chemistry
  • Immunofluorescence
  • _______blot
  • ELISA
  • Lateral _____ test
  • Hemagglutination
A
  • Focus forming assay
  • Immunohistochemistry
  • Immunofluorescence
  • Immunoblot
  • ELISA
  • Lateral flow test
  • Hemagglutination
136
Q

Name a few laboratory methods of viral antigen identification.

  • Focus forming assay
  • Immunohistochemistry
  • __________escence
  • Immunoblot
  • _____
  • Lateral flow test
  • ____________
A
  • Focus forming assay
  • Immunohistochemistry
  • Immunofluorescence
  • Immunoblot
  • ELISA
  • Lateral flow test
  • Hemagglutination
137
Q

What test can be used to check whether a viral infection is acute or chronic?

A

Antibody tests

(IgM and IgG checks)

138
Q

What laboratory method is used for direct identification of viral infections?

A

Electron microscopy

139
Q

What rapid method of viral laboratory identification does not involve any visualization (direct or indirect) of the pathogen / culture changes / fluorescence but involves the viral genetic material?

A

PCR

T1 - Phase 2 - Systems Modules (I) (27 decks)

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