Final Exam Flashcards
1
Q
when was influenza first described
A
400 BC
2
Q
t/f
virologists believe another influenza pandemic that could kill millions is inevitable
A
true
3
Q
most diseases are caused by _____ viruses
A
rna
4
Q
why did influenza epidemics become unmanageable at alarming speeds (3)
A
short incubation period (1-4 days)
one droplet can contain 100,000-1,000,000 virus particles
5
Q
what is the approximate R0 of influenza
SARS-CoV2
A
1.4
2-3
6
Q
who normally dies from influenza
why
A
babies and elderly
bc their immune systems are either not fully developed or no longer function at their prime
7
Q
what is a hallmark clinical symptom of influenza
how long does it last
A
fever (100-103 degrees)
3-4 days
8
Q
how long does it typically take for flu symptoms to clear themselves up
A
7 days
9
Q
what two secondary infections lead to death after a flu infection
A
bronchitis
pneumonia
10
Q
t/f
flu infections tend to have age-dependent side effects
A
true
11
Q
what three secondary infections are common for young children with the flu?
elderly?
A
croup, secondary bacterial pneumonia, middle ear infections
life-threatening secondary pneumonia, worsening of preexisting conditions (like heart failure)
12
Q
what is the family name for influenza
what are the three main genera
A
Orhtomyxoviridae
Alpha, Beta, Gamma
13
Q
what type of virus is influenza (segemented vs nonsegmented; +/-)
A
neg ssRNA, segmented
14
Q
t/f
only Influenza A can infect humans
A
false
A, B, and C can infect humans
15
Q
which influenza is rare
A
C
16
Q
t/f
being infected with one type of flu protects you from the others
A
false
17
Q
Name that flu boo: infects humans and animals goes through antigenic shift and drift can cause pandemic that mostly affect young people 8 gene segments 10 viral proteins with unique M2
A
influenza A
18
Q
Name that flu boo: humans only antigenic drift only leads to severe typically in at risk and elderly doesn't cause pandemics 8 gene segments 11 viral proteins, unique NB
A
influenza B
19
Q
Name that flu boo: humans and piggies antigenic drift only mild disease, common in kids 7 gene segments 9 viral proteins, unique HEF
A
influenza C
20
Q
Am I driftin' or shiftin' slow gradual change responsible for localized/ seasonal epidemics by A, B, and C mutation in H and N subtypes --------------------------- sudden dramatic change cause pandemic influenza A only viral re-assortments leading to novel flu virus
A
antigenic drift
antigenic shift
21
Q
what is the animal reservoir for Influenza A
are they symptomatic or asymptomatic
A
wild water fowl
asymptomatic
22
Q
what are the two tests for laboratory diagnosis of the flu
A
ELISA tests
RT-PCR
23
Q
Name that testing method (flu):
some distinguish between A and B
results in 10-20 minutes
LOW SENSITIVITY HIGH SPECIFICITY
A
ELISA assay
24
Q
Name that testing method (flu): used to confirm conventional virus isolation detection in cell cultures expensive results take 2-10 days
A
RT-PCR
25
Outline Flu Pathogenesis Here
1. transmitted by droplets
2. virus gets into respiratory tract
3. virus attaches to the ciliated columnar epithelial cells lining the sinuses and airways
26
what is the primary site of infection in someone infected with the flu
tracheobronchial tree and nasopharynx
27
what happens to the cilia in the respiratory tract as the flu virus replicates
what does this lead to....
they are destroyed
1. lungs aren't cleaned well
2. mucus stays in the airway and causes coughing
3. lead to secondary infections
28
what two proteins can we develop immunity to on the surface of the flu virus
N: neuraminidase
H: hemagglutinin
29
Antibodies against _____ neutralize the flu virus and those against ______ do not neutralize, but can help with the reduction in the release of the virus from infected cells
H
| N
30
immediately after isolation flu particles are _____ in shape, but after several passages they're _____
filamentous
| spherical or pleomorphic
31
who am i:
enveloped
80-120 nm
12-14 kb
influenza A
32
how many subtypes of H and N are found in influenza A
| how many proteins particles on the surface of the virus
18; 11
| 400; 100
33
name the 6 proteins that make up Influenza A
| what do they do
1. M1 matrix- wraps around rna
2. M2 ion channel-lets in hydrogen ions
3. NP- nucleoprotein around RNA
4. PA, PB-1, PB-2 -RdRp
5. NS-1- blocks IFN and stops cellular mRNA from leaving nucleus preventing translation
6. NS-2- helps viral RNA out of the nucleus
34
how is a flu virus is named (in order)
1. influenza type
2. species isolated from (unless human)
3. place of isolation
4. strain of designation
5. year of isolation
6. H and N subtype number
35
when naming a flu virus do you designate the H and N subtype if it's B or C
no
36
what leads to antigenic drift
changes in H and/or N because viral RdRp does not have a proofreading mechanism
37
what causes antigenic shift
two versions of influenza A co-infect a cell and lead to a virion product with a combo of gene segments
38
t/f
| mutations are common in influenza A viral infections
true
39
____ cleaves virus from sialic acid so that when the virus is released it does not reattach to the infected cell
neuraminidase
40
why doesn't avian flu infect people
because the H proteins struggle to attach to the sialic receptor
41
which season is the flu more prevalent in?
| why? (include humidity and temp in explanation)
winter
aerosol spread easier at 20% humidity and temperatures of 5 C or 41 F
people are closer together in contained spaces
42
what unique effects were seen with the 1918 Spanish Flu
killed 20-40 year olds
killed in 2-3 days
hemorrhagic symptoms
43
what spread faster than any plague in history
1918 spanish flu
44
what was the precursor to the spanish flu
an avian flu strain
45
what antivirals are used to treat the flu
| what do they do
M2 inhibitors- prevent uncoating
| N inhibitors- prevent neuraminidase from cleaving sialic acid during budding
46
what is the most effective way to prevent the flu
vaccine
47
what are the 2 flu vaccines
Trivalent: 2 strains A and 1 strain B
Quadrivalent: 2 strains A and 2 strains B
48
```
name the flu viral RNA:
shorter than template genome
has poly A tail
5' cap
synthesis is insensitive to protein synthesis inhibitors
```
+ viral mRNA
49
```
name the flu viral RNA:
exact copy of genome segment
no poly A
no 5' cap
synthesis requires continuous viral protein synthesis
```
+ antigenome/viral copy RNA
50
what family does the flu virus belong to
orthomyxoviridae
51
what family does rabies virus belong to
rhabdoviridae
52
```
name that virus family:
monopartite
15-16 kb
helical
enveloped
virion size: 150-200 nm
```
paramyxoviridae
53
what two viruses fall under the family paramyxoviridae
measles morbillivirus
| mumps orthorubulavirus
54
1. what is the common name for measles morbillivirus
2. what is the R0 for this virus & how is it spread
3. incubation period
4. what appears about 2-3 days in
5. when does a rash that appears on the face that eventually spreads downward
1. rubeola
2. 12-18; respiratory
3. 7-14 days
4. Koplik spots-- white spots in the mouth
5. 3-5 days
55
t/f
| you can shed rubeola (measles) 2 days prior to and post symptom appearance
false
| four
56
for what age group is measles most serious
5-20
57
______ leads to death or neurological complications after infected with measles
encephalitis
58
what effect does rubeola have on pregnant women
can lead to babies with low birth weight or premature birth
59
______ occurs _____ yearspost measles at a rate of about 1/10,000 and can lead to death in __-__ years.
SSPE Subacute Sclerosing Panencephalitis
7-10
1-2
60
what is a hallmark symptom of mumps orthorubulavirus
what is the incubation period
how is it spread
swollen salivary glands
16 days
respiratory
61
who tends to experience the most complications from mumps but is typically rare
adults
62
```
name that family:
monopartite
19 kb
helical
enveloped
80 and 650-1400 nm
```
filoviridae
63
what two viruses (genera) fall under filoviridae
| which genera was discovered first
ebolavirus
marburg marburgvirus
marburg
64
when and where was marburg marburg virus discovered
1967 in marburg, germany
65
what are the five species of ebolavirus
which infect humans
which infect primates
bundibugyo, reston, sudan, tai forest, zaire
b, s, z, tf
r
66
what is the mortality rate for ebolaviruses
| which one has the highest mortality rate
40-80 %
| zaire
67
which ebola virus was discovered by an outbreak at a facility in DC that was transmitted via respirator droplets that only caused disease in primates
reston
68
how is ebola typically transmitted
| what is the animal reservoir
direct contact with body fluid of infected peoples
| fruit bats or primates
69
all about ebolavirus:
1. incubation period
2. how long does it last
3. when and where was the first outbreak
2-21 days
10 days- 2 wks
1976 in Democratic Republic of the Congo
70
infectious proteins with no genetic material that cause a group of diseases of the brain and nervous system
prions
71
what is the name of the brain and nervous system diseases that prions cause
Transmissible spongiform encephalopathies
72
disease that causes a noninflammatory process that results in vacuolation or spongiosis of GREY matter in the brain
tse
| transmissible spongiform encephalopathies
73
small pathogenic RNA that has no proteins that cause virus like diseases in plants
viroids
74
what is the first recognized TSE
what causes it
where was it seen
when was it seen
Kuru
cannibalism
New Guinea in South Fore people
1950s-60s
75
Name that prion disease:
caused by consumption of contaminated beef
survival after symptoms = 13-14 months
variant Creutzfeldt-Jakob disease
| vCJD
76
Name that prion disease:
caused by inherited germline mutation in PrP gene, sporadic, or iatrogenic
survival after symptoms: 4-5 months
Creutzfeldt-Jakob disease
77
Name that prion disease:
caused by inherited germline mutation in PrP gene
survival after symptoms: 2-6 years
Gerstmann-Straussier Scheinker disease
78
Name that prion disease:
caused by inherited germline mutation in PrP gene
survival after symptoms: 12 months
Fatal familial insomnia
79
what are the three stages of symptoms in kuru
ambulant
sedentary
terminal
80
name that kuru symptom stage:
unsteady gait
tremors
loss of coordination
ambulant
81
name that kuru symptom stage:
| can't sit without support, difficulty swallowing, incontinence
terminal
82
```
name that kuru symptom stage:
can't walk without support
jerky movements
outbursts of laughter
depression
```
sedentary
83
what does prion stand for
proteinaceous infectious particle
84
what did stanley prusiner do in 1972
| what did he discover in 1984
initiate research to help isolate agent that cause kuru
| gene that encoded the prion was found in the brain of all animals
85
what year did Wickner discover a yeast prion (Ure2p) that could change shape and cause other yeast proteins to change to a similar shape
1994
86
t/f
| prions are highly resistant to routine methods of decontamination
true!
87
how are instruments used to process prions decontaminated
1 N of NaOH or undiluted fresh household bleach followed by autoclaving at 132 C for 4.5 hours
88
where is PrP the most abundant
how does it contribute to infectious disease
how does it damage nerve cells
neurons
when it is post-translationally misfolded and resistant to protease digestion
by accumulating into clumps
89
which chromosome is the PRNP gene located on
| how long is the protein
chromosome 20
| 254 aa
90
when does the conversion of normal PrP to PrP(res) occur
during the recycling process where PrP is taken into endocytic vesicles and sent back to the cell surface or degraded
91
what three ways can prions invade the brain
1. the vagus nerves from abdomen
2. hypoglossal nerve of the tongue
3. diet
92
what is the average incubation period for TSEs
10-20 years or even 40
93
what are some changes seen in the brain during TSE infection
neuronal loss due to apoptosis
vacuolization
amyloid plaques
94
which prion dieases broke the species barriers and led to vCJD
how did this occur
BSE/bovine spongiform encephalopathies
| there's a high degree of homology between the 2 species
95
what is the proposed origin of BSE
| when was it first diagnosed
cows being scrapie infected sheep organ meat
| 1985
96
when was the first US scrapie case
1947
97
when was the first vCJD epidemic in the UK
1994-1996
98
prion disease found in deer, elk, moose
| transmission occurs directly or indirectly through food or water sources
chronic wasting disease
99
what are some symptoms of cwd
emaciation
excessive thirst/drooling
frequent urination
aspiration pneumonia
100
what % of deer in captivity get CWD
| wild?
15
| more than 90
101
t/f
| plants can act as carriers for CWD and play a role in horizontal transmission
true
102
t/f
| CWD can infect people
false
103
Viroids are __ssRNA and covalently closed circular pathogenic molecules. The have ______ base-pairing and depend upon _____ enzymes for replication and other functions.
+
internal
host
104
what are the two viroid families
avsunviroidae
| pospiviroidae
105
name that viroid family:
branched, quasi rodlike structure
accumulate and replicate in chloroplast
avsunviroidae
106
name that viroid family:
true rodlike secondary structure
nuclear localization
pospiviroidae
107
what are the FIVE structural domains of a viroid
```
Central
Pathogenicity
Variable
Terminal domain 1
Terminal domain 2
```
108
name the viroid structural domain:
1. critical for replication and processing
2. highest variability in the sequence
3. role in viral movement
4. symptoms of viroid infected plaints
1. central
2. variable
3, terminal domains 1 and 2
4. pathogenicity
109
what enzyme synthesizes viroid RNA
cell's DNA dependent RNA polymerase 2
110
what was the FIRST viroid characterized
when
what does it infect
Potato spindle tuber viroid
1971
tomatoes and potatoes
111
what creature are you most likely going to contract rabies from in the US
what is the primary reservoir of rabies in the eastern shore
bat!
| raccoons
112
how does rabies travel to the brain
bite----->muscle---->PNS---->CNS----->brain
113
In ___/____ Pasteur and Roux developed an attenuated rabies vaccine using dried strips of spinal cord from infected rabbits. The first animal was tested on was a ___. In ____ they tested the vaccine on a 9 year old boy
1884-1885
dog
1886
114
when were rabies vaccine animal baits for wildlife implemented in the US
1990s
115
1. what are the two forms of rabies
2. incubation period
3. how many days before coma
4. when does death occur
1. furious (encephalitic) and paralytic (dumb)
2. 5 days-several years (furious); 2-3 months for paralytic
3. 2-14 days
4. 18 days after symptoms
116
am i furious or paralytic rabies:
1. reclusive behavior, drooling and salivation, startled by sudden noise
2. excitation, aggressiveness, biting stuff
1. paralytic
| 2. furious
117
am i furious or paralytic rabies:
1. hydrophobia, difficulty swallowing, hallucination, hypersalivation, jerky movements
2. NO hydrophobia, NO seizures, NO hyperactivity, weakness
1. furious
| 2. paralytic
118
when are routine rabies tests performed
antemortem (before death)
119
what are medical professionals looking for when they do skin punch biopsies at the nape of the neck
Ag in cutaneous nerves at the based of hair follicles
120
what sort of immunization do individuals who do rabies testing have to receive?
what about those who are exposed to rabies
pre-exposure prophylaxis
| post-exposure prophylaxis
121
there are less than ___ known human survivors who received pre/post exposure rabies prophylaxis
when was the first recorded survivor
20
| 2004
122
how was the first rabies survivor treated
without PEP
| treated using Milwaukee protocol using drug induced coma and antivirals
123
tell me about the pre exposure prophylaxis
- dose (as well as days given)
- how long to induce immunity
- how long does it last
3 doses on days 0, 7, 21, or 28 intramuscularly
7-14 days
2 years
124
immunization consists of antibodies from vaccinated blood donors
post exposure prophylaxis
125
what type of immunity does post exposure prophylaxis confer
passive until the antibodies kick in to confer active immunity
126
which form of the post-exposure prophylaxis vaccine is given if the person exposed to rabies has never been vaccinated?
what if the have been vaccinated before
4 dose on day 0, 3, 7, 14
2 dose on day 0 and 3
127
what family does rabies belong to
| genus
rhaboviridae
| lyssavirus
128
```
name that virus:
unique bullet shape
75 nm wide and 180 nm long
covered in glycoproteins
helical
enveloped
```
rabies
129
what is the purpose of the matrix protein in rabies
hold onto the genome
130
what proteins make up RdRp in rabies virus
L and P
131
tell me about rabies:
how long is the genome
+ or - ssRNA
how many genes
12 kb
-ssRNA
5
132
when did HIV appear and what other symptoms popped up with it
when was the first HIV1 sample found in blood
```
1980s
Kaposi's sarcoma (skin cancer)
CMV
pneumonia cased by atypical bacteria
1959
```
133
What did Gallo and Montagnier contribute to the discovery of HIV
described a retrovirus isolated from T helper lymphocytes from a AIDS patient with lymphadenopathy
134
which strain of HIV is less infectious, rare in the US and progresses more slowly to AIDS
HIV2
135
what is the HIV-1 Hunter Theory
HIV began as a zoonosis that from SIV which infected chimp that crosses the species barrier when hunters killed and ate chimp meat
136
how is HIV spread
| can it be spread by mosquitoes
via direct contact with body fluids ie blood, semen, vaginal fluids, and breast milk
nope
137
___ and ___ easily disrupt HIV because it is enveloped. It is also ___ susceptible to drying out
soap
water
highly
138
globally, ___% of people do not know they have HIV. In the US __% do not know
25
| 14
139
what cells does HIV destroy
CD4+ Th lymphocytes
140
what are the phases of an HIV infection
primary infection (acute)
chronic asymptomatic
AIDS
141
name that stage of HIV infection:
starts 2-4 weeks after infection
happens between appearance of detectable HIV RNA and the first detection of antibodies
CAN BE ASYMPTOMATIC
acute infection
| acute retroviral syndrome
142
which primary antigen is found in high abundance during infection and is part of the nucleocapsid for HIV
p24
143
name that stage of HIV infection:
neither signs or symptoms are present
fully developed positive IgG response
progress to AIDs in 10-12 yrs w/o treatment
clinical latency or chronic asymptomatic
144
name that stage of HIV infection:
| CD4+ Th lymphocyte count below 200 cells/uL and one or more opportunistic infections
AIDS
145
how are AIDS patients treated
antimicrobial prophylactic treatments
146
when was HIV first isolated
when were the first detection tastes made available
how does one test for HIV
1983
1985
using an ELISA test look for antibodies in the blood or testing for viral nucleic acid or p24 antigen
147
what family does HIV belong to
| genus
retroviridae
| lentivirus
148
```
2 +ssRNA (10 kb)
100 nm icosahedron-like
gp120 and gp41 surface proteins
reverse transcriptase(p64) and integrase(p32)
protease(p10)
```
HIV
149
where is the protease in HIV bound?
reverse transcriptase?
integrase?
nucleocapsid
viral genome
viral genome
150
HIV infects ____ early in disease and ____ later in disease
| why
macrophages; CD4+ Th lymph
because they have a high affinity for CCR5 coreceptor on macrophages in the beginning and high affinity for CXCR4 coreceptor on T lymphocytes later
151
what initiates DNA synthesis in HIV
tRNA lysine
152
what are the three regions in a retrovirus
gag
pol
env
153
what are the accessory proteins in HIV and what do they do
tat- enhances viral mRNA transcription
rev- controls mRNA exit from nulceus
nef and vpu- downregulate CD4 to prevent reattachment
154
fusion of cells that lead to multiple nuclei and causes cellular death in HIV
syncytia
155
what is the smallpox hypothesis in terms of human genetic resistance to HIV
some environmental stressor (ie smallpox) led to there being a higher incidence of people to be either homozygous or heterozygous for the CCR5 defect that contributes to resistance against HIV
156
what is the defect that makes people HIV resistant
| what does it do
CCR5 -32
| it is a truncated protein that prevents the gp120 and gp41 proteins from binding the cell
157
how many classes of gene therapy are there for HIV
| what are they
6
1. nucleoside analog reverse transcriptase inhibitor
2. non nucleoside ""
3. protease inhibitor
4. fusion inhibitor
5. CCR5 blocking entry inhibitor
6. integrase inhibitor
158
outline the steps for HIV replication
1. gp12o binds CCR5 cell receptor
2. gp120 and 41 go through conformational change where gp41 becomes coiled and hooks virus and cell membrane together leading to uncoating
3. genetic material enters cytoplasm and is replicated via reverse transcriptase which uses trna lysine as primer
4. viral dna gets transported to the nucleus and inserted into a chromosome hotspot using p32 (integrase)
5. virus is transcribed in to 9 kb long mRNA strands using cell dependent machinery
6. gag and gag-pol proteins are translated into long polyproteins and env proteins a glycosylated in the golgi and then cleaved into gp120 and gp41 before getting sent to the cell membrane surface
7. virion is assembled at budding site and gag/gag-pol proteins are cleaved to make a mature virus particle
159
outline flu replication
1. H protein binds sialic acid receptor and enters via rme
2. uncoating occurs to due low pH
3. M2 proteins allows for the influx of H ions which disrupt the M1 matrix around the RNP releasing RNP into the cytoplasm
4. viral gene segments (RNP) enter the nucleus
5. PA and PB1&2 remove 5' caps and 10-13 nucleotides from cellular mRNA and attach it to viral genome
6. 10-13 nt are used for transcription primer by cell dependent RNA poly 2
7. H, N, and M2 proteins are folded and glycosylated in the ER before being transferred to the Golgi for assembly
8. virus leaves via budding
160
outline rabies replication
1. binds nicotinic acetylcholine receptor and enters via rme
2. drop in pH leads to uncoating and nucleocapsid enters the cytoplasm
3. virus travel to neuronal neuronal body to begin replication and transcription
4. L and P protein transcribe viral genome and in +ssRNA transcripts for each gene and L gives each a poly A tail and cap
5. N, P, M, L are translated by free ribosomes and G is translated by membrane bound ER ribosomes and posttranslationally modified at the Golgi
6. virus is released via budding when enough -ssRNAs, L, N, and P proteins have accumulated
161
what is the primer used in flu replication
the 10-13 nucleotides snatched by PA and PB1&2
162
when does the synthesis of full length +ssRNA begin in rabies genome replication
when there is enough N protein available
163
how many copies of genomic -ssRNAs produced per one +ssRNA copy in rabies
50
164
what type of protease cleaves the env protein in HIV
| gag and gag-pol
cell
| HIV specific
165
how many pieces is the 9kb mRNA polyprotein product spliced in to in HIV
how many promoters are used
30
| 1
