Viruses Part 1 Flashcards
1
Q
Viruses is Latin for
A
Poison
2
Q
Viruses infect
A
bacteria, fungi, plants and animals
3
Q
In 1892, Iwanoski- tobacco mosaic virus (TMV)
A
Filtrate of diseased plant contained infectious material
Filtrate did not contain bacteria…smaller than bacteria
4
Q
1898- Beijernick- continued TMV experiments
A
Last plant contaminated as severely as the first
Infectious material replicating inside plant
5
Q
Viruses are
A
Obligate intracellular parasites
Requires a host
Not living
6
Q
In order for viruses to replicate what they must do?
A
Infect a living cell
7
Q
Viruses cannot grow on
A
Agar plates
8
Q
Virus that infects a bacteria
A
Bacteriophage
9
Q
Viruses are macroscopic. (T/F)
A
False, they are microscopic.
10
Q
Viruses are how small?
A
<0.3 um, filterable
11
Q
“Filterable agents”
A
viruses, they will go through most filterable papers
12
Q
To see a viruses you need a
A
ELECTRON microscope
13
Q
Do viruses have both DNA and RNA?
A
NO, but there are DNA viruses and RNA viruses.
14
Q
What components of the cell does the virus use to replicate?
A
Energy, ATP, neucltodides, enzymes
15
Q
The extra layer protecting viruses
A
Capsules
16
Q
Two bacteria similar to viruses
A
Rickettsias and chlamydias
17
Q
Are viruses sensitive to antibiotics?
A
NO, they are ineffective.
18
Q
Complete infectious particle
A
Virion
19
Q
Contain a single type of nucleic acid
A
Genome
20
Q
Can DNA and RNA be double stranded and single stranded?
A
Yes, very different from bacteria.
21
Q
Three classifications of structure
A
Based on nucleic acid content
Capsid
Envelope
22
Q
Envelopes are made of
A
Phospholipids
23
Q
Capsules are made of
A
Proteins
24
Q
Enveloped viruses
A
Viruses that have envelopes
25
Nonenveloped viruses or naked viruses
Viruses that do not have envelopes
26
Ss RNA genomes have a ____.
Polarity
27
A negative sense RNA does not have the message to make proteins it must first be copied to be a ____.
Positive
28
Can go in the cell and directly function as mRNA
+RNA
29
Must first be transcripbed into a +RNA strand which then serves as the mRNA
-RNA
30
RNA transcribed into DNA inside the host
Retroviruses
31
Example of a Retrovirus
HIV
32
In rabies viruses what is the capsule shaped as?
A bullet
33
Do all viruses have capsules surrounding their nucleic acids?
yes
34
Three shapes of viruses
Helical
Polyhedral
Complex
35
Protein coat surrounding the nuclei acid
Capsid
36
Each capsid is composed of units called
Capsomers
37
Do capsomers have just one protein?
Yes and no. May be of one protein of several different proteins.
38
Describe helical symmetry
look like a long rod
Many copies of the same protein wrapped in a helix
Nucleic acid surrounded by hollow, helical, cylindrical capsid
39
Two examples of nucleic acid surround by a hollow, helical, cylindrical capsid
TMV (tobacco mosaic virus) and rabies virus
40
Polyhedral symmetry
Many sides
41
Complex symmetry
complicated structures, often bacteriophages
42
Isoachedral
regular polygon with 20 sides with 12 corners
Each side- equilateral triangle
43
Three viruses of Isoachedral
Polio, adenovirus, herpes virus
44
Bacteriophages have what three things?
Capsid, tail and sheath
45
Does the pox virus have a capsid
no
46
Example of spikes
COVID
47
Viral glycoproteins found in many envelopes are called
Peplomers or spikes
48
Classified by host
Plant, animal, or bacteriophage
49
classified by disease caused
Respiratory diseases, enteric viruses
50
Classified according to structure
Nucleic acid type, replication strategy, morphology
51
Viridae=
Family
52
“Species” -
Group of viruses
53
What qualifies a virus in a species?
Have same nucleic acid and infect same host cells
54
6 DNA families of viruses
Parvoviridae, andenoviridae, papovaviridae, proxviriade, hepadnaviridae, herpesviridae
55
The Human parvovirus, B19 is an example of
Parvoviridae
56
Parvoviridae causes
gastroenteritis, fetal death, fifth disease
57
Are viruses prokaryotes or eukaryotes?
NEITHER
58
Causes respiratory diseases
Adenoviridae
59
PA- papilloma causes
Warts
60
PO- polyoma causes
tumors
61
The only virus Family that has ssDNA
Parvoviridae
62
VA- vacuolating causes
Causes vacuoles in host
63
HPV causes
Warts, cervical cancer
64
HPV is an example of what family
Papovaviridae, VA- vacuolating
65
Largest of all of the the viruses
Poxviridae
66
What is unique about small pox?
The only disease completely eradicated from the world.
67
Two examples of poxviridae
Smallpox virus (variola) and cowpox (vaccinia)
68
Hep B virus is an example of what family
Hepadnaviridae
69
Monkey pox is part of what family
Poxviridae
70
Very large viruses, become latent, ubiquitous in animals
Herpesviridae
71
HHV 1 and HHV 2 examples and what it does
Simplexvirus; causes cold sores and genital herpes
72
Can you be cured from a herpes virus?
NOOOOO, it cannot leave your body! It can laying dormant and reactivated again and again.
73
What does latent mean?
Never leave the body, lays dormant and can be reactivated OVER AND OVER AGAIN
74
What can activate a latent virus?
Immuosupression, stress, surgeries, etc.
75
HHV 3 example and causes
Varicellovirus; causes chicken pox, shingles
76
HHV 4 viruses and causes
lymphocryptovirus- EBV (Epstein Barr virus) Causes mononucleosis
77
HHV 6 and HHV 7 virus
Roseolovirus
78
HHV 5 virus
Cytomegalovirus
79
HHV 8 virus and causes
Rhadinovirus; causes Kaposi’s sarcoma
80
How are herpes simplex infection transmitted
Oral or respiratory tract
81
Causes cold sores
HHV 1
82
HHV 1 lay dormant in what
In trigeminal nerve ganglion
83
HHV 1 or HHV 2 is sexually transmitted
HHV 2
84
HHV 2 lays dormant in
Sacral nerve ganglion
85
Genital herpes is HHV 1 or 2
2
86
What can also cause genital herpes
HSV 1
87
Symptoms of genital herpes
Vesicles at site of entry - 1 week after exposure
Vesicle are infectious and painful
Virus is latent in sacral ganglia— reactivates—new vesicles
Reactivating occur from stress, hormonal changes, illness
88
Neonatal herpes is HHV 1 or HHV 2
2
89
How are neonatal herpes transmitted
Cross the placenta and infect fetus, or infant acquires during birth IF mother has blister time of delivery
90
RNA families of viruses
Pricornaviridae, togaviridae, coronaviridae, orthomyxoviridae, flavivridase, retroviridae, Paramyxoviridae, rhabdoviridae, fliboviridae, Reoviridae
91
PICO =
Very small
92
3 examples of viruses under picornavirdidae family
Coxsackieviruses, enteroviruses, rhinoviruses
93
rhino=
Nose
94
Example of an enteroviruses and what it effects
Intestines, Hep A (HAV)- acute hepatitis
95
Rhinoviruses are the
Common cold
96
COVID 19 is from where
China
97
How is COVID transmitted
Droplets and airborne
98
The VERY distinctive symptom of COVID 19
Loss of taste or smell
99
TOGA=
Cloaked or enveloped
100
How are togaviridae transmitted
Arthropods (mosquitoes)
101
Two examples of togaviridae viruses
Arboviruses
Rubiviruses
102
Rubivruses are transmitted by
Respiratory
103
Rubella is under what virus and what is it
German measles, Rubiviruses
104
Example of arboviruses
Encephalitis viruses
105
Examples of coronaviridae
Common cold, SARS-CoV, MERS-CoV, SARS-CoV2 (COVID-19)
106
3 FDA approved for emergency use (USA) for COVID-19
1. Pfizer: m-RNA
2. Moderna: m-RNA
3. Johnson and Johnson: viral vector
107
Can RNA go into the nucleus of the cell?
NO
108
Influenza is under what family of RNA
Orthomyxoviridae
109
“Straight”
Orthomyxoviridae
110
Is orthomyxoviridae segmented?
Yes
111
Is orthomyxoviridae enveloped?
Yes
112
Can infect swine, birds, and horses.
Influenza A
113
SS RNA is divided into how many segments?
8
114
Type B influenza is mainly in
Animals
115
The most common type of Influenza is what and found where?
Type A, found in animals and humans
116
What shape is the 8 segments of ssRNA?
Helical
117
The protein spikes are called
Peplomers
118
H=
And its role
How many variations
Hemagglutinin
Attachment
18
119
N=
And its role
How many variations
Neuraminidase
Release from host cell
11
120
Two types of changes in influenza antigenic variations.
Antigenic drift
Antigenic shift
121
Antigenic drift
Small point mutations affection the H and N constantly. The new subtype is slightly different than the parent and is usually responsible for the new epidemics or sales occurring yearly.
122
Antigenic drift affects what Peplomers?
H and N
123
Antigenic shift
A sudden and major change in the H and/or N antigens creating a new strain. This is due to a major recombination occurring when 2 stains of viruses infect the same cells.
124
Usually cause pandemics
Antigenic shift
125
(Think of pigs) Usually the best mixing vessel for antigenic shifts.
Swine cell
126
Antigenic shift affects what Peplomers?
H and/or N
127
the “mixing bowl” for reassortment of avian and human viruses.
Pigs
128
UNTIL NOW _____ is unable to efficiently effect humans.
Bird flu
129
Where did the Spanish Flu originate from?
US of A
Likely Kansas
130
What does the 1918 influenza virus cause
Severe viral pneumonia
Came on in just a few days, death shortly follows
Lungs massively hemorrhaged or filled with fluid
131
The 1918 Spanish Flu has higher activation of genes with
T-cells and macrophages
Tissue injury, oxidative damage, apoptosis
132
Apoptosis
The death of cells which occurs as a normal and controlled part of an organism's growth or development
133
What induced a cytokine storm?
The 1918 Spanish flu
134
H1N1 is AKA
Swine flu
135
Prevention of Swine flu
Killed and live attenuated vaccines are available
136
Which major virus of 2009 had a low mortality rate but an extremely high infection rate?
H1N1 (swine flu)
137
Influenza is transmitted by
Droplets and hands
138
How does the influenza virus attach
Via H to Salic acid receptors on cells
139
What happens within 1-3 days of influenza infections
Cytokines release
This causes:
Chills, fever, malaise, muscle aches, runny nose and cough
140
Neuraminidase inhibitors AKA
Tamiflu
141
What does tamiflu do
The replication is blocked by neuraminidase inhibitors which prevents virons from being released from the surface of infected cells.
142
How are influenza vaccines grown
In eggs or in a cell culture
143
What will you be asked when you get an influenza vaccine?
Are you allergic to eggs?
144
Flumist
A live attenuated viral vaccine that is given intranasal for influenza.
145
New vaccines for influenza
Cell based and recombinant H glycoprotein has been approved by the CDC (no whole virus)
146
Why will we never be able to irradiate Influenza?
Because any virus that lives in animals AND humans will always have a reservoir to live in.
147
Other measures (besides vaccinations) for influenza.
Wearing masks
Hand washing
Social distancing
148
Reverse transcriptions
Starts as RNA and changes to DNA
149
The enzyme for reverse transcriptions that makes DNA intermediate to inset into host chromosomes.
Reverse transcriptase
150
Why can’t HIV be cured?
Because the genome of viruses will remain in their DNA forever.
151
RNA tumor viruses
Oncoviruses
152
HTLV-1
Leukemia viruses
153
Three examples of retroviridae viruses
Oncoviruses, leukemia viruses, HVI
154
Paramyxoviridae -a way to remember
“Near” + “mucus”
155
3 paramyxoviridae viruses
Mumps, measles, parainfluenza
156
Rubeola virus
Measles
157
The only DS RNA!!!!
Reovirdiae
158
Reovirdae
R=
Respiratory diseases
159
Reovirdae
E=
Enteric diseases
160
Reovirdae
O=
Orphan- not associated with any diesaes
161
2 Orphan Reovirdae viruses
Rota virus -severe diarrhea in young children
Colorado tick fever virus
