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.
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).
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.
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.)
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)
6
Q
Describe a few of the basic structures that viral capsids can form.
A
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.
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.
9
Q
In order to create a metastable viral capsid, what type of bond usually holds the capsid subunits together?
A
Loose, electrostatic interactions
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
11
Q
Which viral capsule shape is always enveloped?
A
Helical
12
Q
What type of virus has the most complex capsid structure?
A
Bacteriophages
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.
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.
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.
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).
17
Q
A dessicated _________ (naked / enveloped) virus is still infectious.
A
A dessicated naked virus is still infectious.
18
Q
Can a naked or an enveloped virus or both survive within the GI tract?
A
Naked only
(stable)
19
Q
Naked viruses stimulate what immune response?
Enveloped viruses stimulate what immune response?
A
Antibody production;
antibody production, cell-mediated response
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
21
Q
How are enveloped viruses typically transmitted?
(Labile viruses)
A
Droplets,
secretions
(also, transplants)
22
Q
How are naked viruses typically transmitted?
(Stabile viruses)
A
Fomites,
dust,
fecal-oral,
droplets
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).
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.)
25
Describe how viral glycoproteins allow for viral envelope formation from host cell membranes.
Via **matrix proteins**
(mediators of capsid-glycoprotein interactions)
26
What determines viral attachment to and specificity for host cells?
Surface proteins
(capsid proteins or envelope glycoproteins)
27
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)*
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)*
28
No matter their genome structure, all viruses converge at a need to synthesize _______ to alter host function.
No matter their genome structure, all viruses converge at a need to synthesize **_mRNA_** to alter host function.
29
What mnemonic is useful in remembering which viral families are DNA viruses?
DNA viruses are **HHAPPPPy**
## Footnote
***H**epadnaviridae*
***H**erpes*
***A**denoviridae*
***P**oxviridae*
***P**arvoviridae*
***P**apilloma*
***P**ol**y**oma*
30
The mnemonic HHAPPPPy is useful in remembering which viral families are DNA viruses. Name the viruses:
## Footnote
***H**\_\_\_\_\_\_\_\_\_*
***H**\_\_\_\_\_\_\_\_\_*
***A**\_\_\_\_\_\_\_\_\_*
***P**oxviridae*
***P**arvoviridae*
***P**apilloma*
***P**ol**y**oma*
## Footnote
***H**_epadnaviridae_*
***H**_erpes_*
***A**_denoviridae_*
***P**oxviridae*
***P**arvoviridae*
***P**apilloma*
***P**ol**y**oma*
31
The mnemonic HHAPPPPy is useful in remembering which viral families are DNA viruses. Name the viruses:
## Footnote
***H**epadnaviridae*
***H**erpes*
***A**denoviridae*
***P**\_\_\_\_\_\_\_\_\_*
***P**\_\_\_\_\_\_\_\_\_*
***P**apilloma*
***P**ol**y**oma*
***H**epadnaviridae*
***H**erpes*
***A**denoviridae*
***P****_oxviridae_*
***P****_arvoviridae_*
***P**apilloma*
***P**ol**y**oma*
32
The mnemonic HHAPPPPy is useful in remembering which viral families are DNA viruses. Name the viruses:
## Footnote
***H**epadnaviridae*
***H**erpes*
***A**denoviridae*
***P**oxviridae*
***P**arvoviridae*
***P**\_\_\_\_\_\_\_*
***P**\_\_\_\_\_\_\_*
## Footnote
***H**epadnaviridae*
***H**erpes*
***A**denoviridae*
***P**oxviridae*
***P**arvoviridae*
***P**_apilloma_*
***P**_ol**y**oma_*
33
All DNA viruses are \_\_\_\_\_\_\_\_-stranded, except for the _________ family.
All DNA viruses are **_double_**-stranded, except for the **_Parvoviridae_** family.
34
All DNA viruses are ________ (shape), except for the _________ family.
All DNA viruses are **_icosahedral_**, except for the **_Poxviridae_** family.
35
All RNA viruses except for the _________ family are \_\_RNA.
All RNA viruses except for the **_Reoviridae_** family (dsRNA) are **_ss_**RNA.
36
Most viruses only have one copy of their genome.
What type of virus has two?
Retroviruses
37
All viruses must produce ______ to be translated by the host **ribosomes**.
All viruses must produce **_mRNA_** to be translated by the host **ribosomes**.
38
What are the phases of viral growth as represented on a graph showing infectious virions per cell (Y-axis) and time (X-axis)?
1. **Eclipse** period
2. **Exponential growth** period
39
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?
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**
40
List the major steps of the viral lifecycle:
1. \_\_\_\_\_\_\_\_\_\_\_\_\_
2. \_\_\_\_\_\_\_\_\_\_\_\_\_
3. Uncoating
4. Synthesis
5. Assembly
6. Release
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
41
List the major steps of the viral lifecycle:
1. Adsorption
2. Penetration
3. \_\_\_\_\_\_\_\_\_\_\_
4. \_\_\_\_\_\_\_\_\_\_\_
5. Assembly
6. Release
List the major steps of the viral lifecycle:
1. Adsorption
2. Penetration
3. **_Uncoating_**
4. **_Synthesis_**
5. Assembly
6. Release
42
List the major steps of the viral lifecycle:
1. Adsorption
2. Penetration
3. Uncoating
4. Synthesis
5. \_\_\_\_\_\_\_\_\_\_\_
6. \_\_\_\_\_\_\_\_\_\_\_
List the major steps of the viral lifecycle:
1. Adsorption
2. Penetration
3. Uncoating
4. Synthesis
5. **_Assembly_**
6. **_Release_**
43
**True/False**.
During the eclipse period of the viral lifecycle, only viral fragments are present inside the host cell.
**True**.
Uncoating of the genome has occurred and no complete virions are detectable until new virions have been synthesized and assembled.
44
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 **_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.
45
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 **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.
46
**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.
**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.
47
Viral adsorption describes viral __________ coming into contact with cell \_\_\_\_\_\_\_\_\_\_.
Viral adsorption describes viral **_proteins_** coming into contact with cell **_surface proteins_**.
*(E.g. HIV surface proteins interacting with TH cell CD4 and CXCR4)*
48
How do naked viruses typically penetrate the cell?
And enveloped viruses?
Direct penetration OR endocytosis;
membrane fusion OR endocytosis
49
What does it mean that viruses in the Hepadnaviridae family have 'gapped' DNA?
Their genome is a mix of single- and double-stranded DNA
50
All viral ssDNA or gapped DNA must be converted to _______ in the host nucleus before it can be transcribed to **mRNA**.
All viral ssDNA or gapped DNA must be converted to **_dsDNA_** in the host nucleus before it can be transcribed to **mRNA**.
51
Ribsome-ready mRNA from a virus is termed \_\_\_\_\_\_\_\_-sense, meaning it is ready for immediate translation.
Ribsome-ready mRNA from a virus is termed **_positive_**-sense, meaning it is ready for immediate translation.
52
Viral RNA and DNA __________ of (+) strands are (-) strands.
Viral RNA and DNA **_complements_** of (+) strands are (-) strands.
53
**True/False**.
Positive-sense RNA are ready for translation.
**Not necessarily!**
Positive-sense ***m***RNA are ready for translation, but some positive sense RNA may need adjustment first.
54
Cells do not make \_\_\_\_\_-dependent RNA polymerase, but viral genomes do.
Cells do not make **_RNA_**-dependent RNA polymerase (**RdRp**), but viral genomes do.
55
(I) If viral dsDNA enters a host cell, what happens next?
*(1st of 7 options in the Baltimore system)*
(I) Immediate transcription to mRNA
56
(II) If viral positive-sense ssDNA enters a host cell, what happens next?
*(2nd of 7 options in the Baltimore system)*
(II) It is turned into dsDNA; then, transcribed to mRNA
57
(III) If viral dsRNA enters a host cell, what happens next?
*(3rd of 7 options in the Baltimore system)*
(III) Immediate transcription to mRNA
58
(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)*
(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
(V) If viral negative-sense ssRNA enters a host cell, what happens next?
*(5th of 7 options in the Baltimore system)*
(V) Immediate transcription to mRNA
60
(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)*
(V) Conversion to dsDNA; then, transcription to mRNA
61
What tool(s) do viral genomes encode to produce **RNA** from **RNA** templates?
**RNA-dependent RNA polymerases** (RdRp)
62
Many viral proteins synthesized from DNA templates are assembled where in the host cell?
The nucleus
63
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.)*
They immediately synthesize it (positive-sense = ready to go);
they bring it with them in the viral capsid
64
What type of genetic material do retroviruses carry?
Positive-sense ssRNA
65
What three roles does reverse transcriptase perform for retroviruses (positive-sense ssRNA)?
1. **ssRNA --\> ssDNA**
2. **ssDNA --\> dsDNA**
3. **Degradation** of original **ssRNA**
66
What main enzyme type allows retroviruses to insert their newly synthesized dsDNA into the host genome?
Integrases
67
What enzyme is required for viral ssRNA to become ssDNA _or_ for viral ssDNA to become dsDNA?
Reverse transcriptase
68
Does viral reverse transcriptase have RNA-dependent RNA polymerase activity or DNA-dependent DNA polymerase activity?
Both
69
**True/False**.
RNA-dependent RNA polymerases and DNA-dependent DNA polymerases are error-prone resulting in high mutation rates.
True.
70
Where do viral RNA genomes typically replicate?
The cytoplasm
71
Does proof-reading occur during viral RNA or DNA replication?
DNA only
(although, poorly done by viral polymerases --- error-prone processes)
72
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?
Cytoplasm;
nucleus
73
What is a procapsid?
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
How can naked virions induce host cell death to be released?
**Necrosis**
* Inhibition of protein synthesis
* Disorganization of cytoskeleton
* Alteration of membranes (Lysosome leak)
**Apoptosis / pyroptosis**
75
How long is the replication cycle for the typical virus (from entering the host cell to thousands of new virions leaving the host cell)?
8 - 36 hours
76
What is antigenic shift?
The **combination of multiple viral species** **to yield a subtype** mix of their collective surface proteins
77
What is antigenic drift?
Naturally accumulated mutations in a viral species over time
78
What are the two potential phases of the bacteriophage lifecycle?
1. **Lysogenic**
2. **Lytic**
79
\_\_\_\_\_\_\_\_\_\_ bacteriophages use both the **lysogenic** and **lytic** phases.
**_Temperate_** bacteriophages use both the **lysogenic** and **lytic** phases.
80
**True/False**.
Bacteriophages in the lysogenic phase are not replicating at all.
**False**.
They replicate passively as the bacteria undergoes binary fission.
81
**True/False**.
Lysogenic phages can carry the ability to form certain toxins between bacterial species.
True.
82
What is the typical causal factor inducing a phage to leave the lysogenic (dormant) phase and enter the lytic (cell death) phase?
**Stress**
(ROS, toxins, bacterial cell damage, etc.)
83
Are respiratory droplets responsible for direct or indirect viral transmission?
Are aerosols responsible for direct or indirect viral transmission?
Direct;
indirect
84
What is the most common route for viral entry into the body?
Respiratory tract
(There are ~100,000 virions per square meter of indoor air!)
85
Why are the eyes poor entry points for infectious agents (assuming the eyes are not damaged)?
Constant washing by **lacrimal** **glands**
+
**IgA**
+
**lysozymes**
86
What term describes the specified spectrum of cells, tissues, or hosts that can be infected by a certain virus?
**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
The stages of viral spread:
**Localized** --\>
\_\_\_\_\_\_\_\_\_\_ --\>
\_\_\_\_\_\_\_\_\_\_
The stages of viral spread:
**Localized** --\>
**Disseminated** --\>
**Systemic**
88
Name some forms of viral routes of spread throughout the body.
**Hematogenous**, **lymphatic**, **neural**,
**fetal** (delivery, breast-feeding, placental)
89
What term describes virus presence in the bloodstream?
Viremia
90
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
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
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
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
Describe how viruses travel up and down neurons.
93
What is a neurotropic virus?
One that can infect neurons
94
What is a neuroinvasive virus?
Can enter the CNS from a peripheral location
95
What is a neurovirulent virus?
One that causes disease of nervous tissue
96
Describe the herpes simplex virus in terms of neurovirulence and neuroinvasiveness.
Neurovirulence: **High**
Neuroinvasiveness: **Low**
*(I.e. it will have very severe effects if it makes it to the CNS, but this is rare.)*
97
Describe the mumps virus in terms of neurovirulence and neuroinvasiveness.
Neurovirulence: **Low**
Neuroinvasiveness: **High**
*(I.e. it often infects the CNS but has few effects.)*
98
Describe the rabies virus in terms of neurovirulence and neuroinvasiveness.
Neurovirulence: **High**
Neuroinvasiveness: **High**
*(I.e. it often spreads from the PNS to the CNS and is usually lethal.)*
99
What is the leading cause of congenital infection?
**CMV**
| (typically asymptomatic)
100
What is the best way for infectious agents to disrupt the basement membrane?
Inflammation
101
Many viruses produce ________ that block interferon production and produce molecules that bind/inhibit \_\_\_\_\_\_\_\_.
Many viruses produce **_miRNA_** that block interferon production and produce molecules that bind/inhibit **_cytokines_**.
102
**True/False**.
Many viruses produce miRNA that promote apoptosis.
**False**.
Many viruses produce miRNA that ***inhibit*** apoptosis.
103
Many viruses downregulate MHC-I (or block ____ or proteasomal activity, etc.) to avoid ____ cells.
Many viruses downregulate MHC-I (or block **TAP** or proteasomal activity, etc.) to avoid **TC** cells.
104
What is an _inapparent_ infection?
Asymptomatic, subclinical
105
**True/False**.
Latent infections often come in recurring rounds.
True.
106
Describe the terms epidemic, endemic, pandemic, and sporadic.
107
3. Ebola virus is more virulent than HPV
(virulences between viruses cannot be compared)
108
How can viral virulence be quantitated?
109
Name a few factors that contribute to the amount of virulence a virus has.
Relative dose, route of innoculation, age, gender, susceptibility of host, etc.
110
What is active viremia?
Viremia produced by active replication
111
Virulence can only be compared among specific viral infections with what relationship to one another?
Viral strains within the same species
(cannot be compared among different viruses)
112
How can a virus be attenuated so that it is safe to give in vaccine form?
Knock out its severe virulence factors
(e.g. remove the neurovirulence from the polio virus)
113
**True/False**.
Only bacteria (not viruses) produce viable exotoxins on any scale large enough to cause obvious signs / symptoms.
**False**.
Many viruses cause significant exotoxin production.
114
Can viral virulence factors be found in untranslated regions?
Yes
115
\_\_\_\_\_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.
**Cyto**lytic 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
Define syncytium.
A multinucleated cell that can result from multiple cell fusions of uninuclear cells
117
What viral process is illustrated in this image?
Syncytium formation
118
**True/False**.
Many viruses can induce the body to release inflammatory vasoactive peptides, bradykinins, histamine, etc.
True.
119
The cytokine storm is an example of auto-damage caused by the _________ (innate/adaptive) immune system.
The cytokine storm is an example of auto-damage caused by the **innate** immune system.
120
What are some examples of of auto-damage caused by the adaptive immune system in response to viral damage?
CD8+-mediated apoptosis;
CD4+ cytokine release
121
Viral poxes and rashes are typically caused by ____ cell activity.
Viral poxes and rashes are typically caused by **TH1** cell activity.
122
In response to viral infection, what cell type calls in eosinophils and may result in lesions?
TH2
123
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?
**B cells**;
**second**: reinfections can lead to antibody-dependent enhancement of viral infections
124
Name some factors affecting host immunocompetence and susceptibility to viral infection.
Host genes (SNPs),
age,
malnutrition,
pregnancy
125
What term describes the release of virions from infected individuals (e.g. in the feces, blood, urine, semen, milk, skin lesions, etc.)?
Viral shedding
126
What percentage of infectious cases seen by physicians are viral in nature?
60%
127
Laboratory testing can be used to do what in relation to viral infection?
**Diagnostic** confirmation;
determination of **antiviral** therapy;
check patient medication **compliance**
128
What are some factors to consider in acquiring a viral sample for laboratory testing?
**Collection site** (oral mucosa, GI tract, urine, etc.)
+
**timing** (stage of disease, viral load, etc.)
+
**proper processing of specimen**
129
What is the gold standard for clinical lab testing of viral infection?
**Viral isolation/culturing**
(Very very sensitive and specific; doesn’t work for all viruses)
130
Besides viral isolation/culturing, what are two other methods of viral lab testing?
Serology;
direct detection methods
131
What do viruses require for laboratory testing?
Living cells
132
What are some drawbacks of viral isolation/culturing in the laboratory setting?
Doesn’t work for all viruses;
often takes several days
133
How do rapid cell cultures for viruses work?
They enhance viral load at cell surfaces for better infection
+
antibody / fluorescent tag added
134
How do viral plaque assays work?
135
Name a few laboratory methods of viral antigen identification.
## Footnote
- _______ forming assay
- \_\_\_\_\_\_\_\_\_\_chemistry
- Immunofluorescence
- \_\_\_\_\_\_\_blot
- ELISA
- Lateral _____ test
- Hemagglutination
- **Focus** forming assay
- **Immunohisto**chemistry
- Immunofluorescence
- **Immuno**blot
- ELISA
- Lateral **flow** test
- Hemagglutination
136
Name a few laboratory methods of viral antigen identification.
## Footnote
- **Focus** forming assay
- **Immunohisto**chemistry
- \_\_\_\_\_\_\_\_\_\_escence
- **Immuno**blot
- \_\_\_\_\_
- Lateral **flow** test
- \_\_\_\_\_\_\_\_\_\_\_\_
- **Focus** forming assay
- **Immunohisto**chemistry
- **_Immunofluor_**escence
- **Immuno**blot
- **_ELISA_**
- Lateral **flow** test
- **_Hemagglutination_**
137
What test can be used to check whether a viral infection is acute or chronic?
**Antibody tests**
| (IgM and IgG checks)
138
What laboratory method is used for direct identification of viral infections?
Electron microscopy
139
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?
PCR
