Influenza and Viral pneumonia-AuCoin Flashcards
1
Q
(blank) is an inflammation of the lungs caused by infection with a virus or bacteria
A
pneumonia
2
Q
Pneumonia is infection of the pulmonary (blank) the (blank) are primarly affected
A
parenchyma
alveoli
3
Q
The inflammation of pneumonia is also caused by (Blank) to infection
A
immune response
4
Q
(blank) is more likley to occur in young children and older adults due to a naive or weakened immune system.
A
Viral pneumonia
5
Q
What are they typical symptoms of pneumonia?
A
cough, fever, chills, SOB
6
Q
What are the common causes of viral pneumonia?
A
- influenza A and B
- RSV
- Parainfluenza virus
7
Q
What does parainfluenza virus cause?
A
croup
8
Q
What are some Less common causes of viral pneumonia?
A
LESS COMMON:
- adenovirus
- rhinovirus
- metapneumovirus
- SARS
9
Q
What are viruses that cause other disease and may cause pneumonia?
A
Herpes simplex virus Varicella-zoster virus Measles Rubella Cytomegalovirus
10
Q
What family does RSV and Human parainfluenza virus belong to?
A
paramyxovirus
11
Q
What are the barriers for respiratory viruses?
A
- Epiglottis and cough reflex (prevent intro of particulat matter in the lower airway)
- Ciliated respiratory epithelium (propels overlying mucous layer upward toward mouth)
- In alveoli (cell mediated immunity, humoral factors, inflammatory response defenf against lower respiratory tract infections )
12
Q
What kind of virus is influenza virus? Is it a DNA or RNA virus?
Is it enveloped?
A
orthomyxo
E
(-)RNA
13
Q
Is influenza common?
How is it transmitted?
A
very common, kills thousands/years: may cause pandemics
respiratory droplets
14
Q
App. (blank) people die of influenza each year in the US
A
36,000
15
Q
What types of influenza causes pandemics?
What type of influenza causes outbreaks?
What type of influenza causes milder infections?
A
A
B
C
16
Q
Influenza A virus has (blank) antigenic types of HA and (blank) types of (NA).
A
16
9
17
Q
What is the reassortment of segments of the genome RNA?
A
antigenic shift
18
Q
What are small mutations in the genome RNA caused by RNA polymerase transciption mistakes?
A
Anitgenic drift
19
Q
Antigenic changes to HA and NA causes (blank and blank)
A
epidemics and pandemics
20
Q
What test can you do to detect the influenza virus?
A
Hemagluttinin assay
21
Q
How long is the incubation period of influenza virus?
A
24 to 48 hours
22
Q
What are the symptoms that develop after the incubation period (24-48 hrs) of orthomyxovirus?
A
DEVELOP SUDDENLY: Fever Myalgia Headache Sore throat Cough
23
Q
WHo are at high risk of getting influenza virus?
A
elderly and those with cardiac or pulmonary disease
24
Q
How long does it take for flu symptoms to resolve from influenza virus? What can complicate this course?
A
4 to 7 days
-pneumonia
25
What does your immunity to influenza virus depend on?
secretory IgA targeting HA in the respiratory tract
26
How do you diagnose inflluenza?
clinically, lab tests are available
27
How do you treat and prevent influenza?
Oseltamivir (Tamiflu) and Zanamivir (Relenza)
| Vaccination (consists of influenza A and B viruses)
28
How does oseltamivir and zamivir treat influenza?
it is a neuramidase inhibitor which prevents the virus from being released from the infected cell
29
What is a well-known complication of influenza?
Bacterial pneumonia caused by Staph aureus
30
How come the influenza virus has a short incubation period?
because it only goes to the lungs and doesnt go anywhere else
31
(blank) illnesses are responsible for more than half of all acute illnesses each year in the US
respiratory illnessess
32
Influenza circulates in the US in the (blank) and (blank)
Fall
| Early spring
33
How come it is difficult to control influenza infection?
mutability and high frequency of genetic reassortment
34
Influenza (blank) is antigenicaly variable and causes the majority of disease. Less antigenic changes occur with influenza (blank). (Blank) is antigenically stable.
A
B
C
35
Influenza A strains are also known to infect (blank, blank, blank and blank)
Aquatic birds
chickens
ducks
pigs
36
What does the influenza virus bind to on a cell to infect it?
sialic acid receptor
37
How does a virus get out of an endosome?
Changes pH to cause the viral envelope to fuse with endosomal membrane and dump its contents into the cell
38
How can you make a negative sense RNA infect a cell?
you need it to bring RNA dependent RNA polymerase with it to make + RNA so that the cell can read it :)
39
What binds to the sialic acid receptor on respiratory epithelial cells?
HA hemagglutinin (HA)
40
What are the 7 steps of influenza virus replication?
1. Receptor mediated endocytosis
2. segmented ribonucleoproteins released into the cytoplasm
3. Genome transported to the nucleus
4. Repliation and transcription
5. Viral mRNAs transported to the cytoplasm for translations
6. Early viral replication proteins transported back to the nucleus
7. Assembly and budding occurs at PM
41
What does the virion contain that allows it to replicate?
RNA dependent RNA polymerase
42
What is unusual about influenza being an RNA virus?
It has its RNA trnscription and relication in the nucleus
| usually RNA viruses dont have both happen here
43
THe (blank) of the endosome facilitates membrane fusion and release of the viral (blank) in the cytosol
low pH
| RNPs
44
Shortly post infection there is a (blank) of host cell protein synthesis
shut off
45
What is the virus encoded RNA polymerase composed of?
What will this do?
What happens to the (+) sense mRNA?
three viral proteins (P proteins) are responsible for transcription
- polymerase will produce (+) sense mRNA from the (-) sense RNA genome
- translated into viral proteins and also used as a template to produce viral (-) sense RNA genomes
46
What is used as a template to produce (-) sense RNA?
(+) sense mRNA
47
What is a ribonucleoprotein (RNP)?
the nucleoprotein (NP) associates with the viral RNA to form a ribonucleoprotein (RNP) structure
48
What are three other encoded proteins bound to the viral nucleoprotein (NP) and what are they responsible for?
PA, PB1, PB2
RNA transcription and replication
49
(blank) forms a shell below the viral membrane which is important for particle assembly.
Matrix protein M1
50
(blank) surrounds the viral particle derived from the plasma membrane of the host cell.
Lipid envelope
51
What 2 glycoproteins are found embedded in the lipid envelope?
Hemagglutinin (HA)
| neuraminidase (NA)
52
HA and HA are exposed as (blank) on the surface of the virus. Why are these 2 surface glycoproteins important?
spikes
| they are the antigens that determine antigenic variation of influenza virus
53
T or F
| 2 distinct influenza viruses may infect a single host cell
T
54
Segmented RNA genomes will be shuffled in this cell creating a new infleunza virus. This process is called (blank). What will this do to the surface antigens?
reassortment
| creates a sudden change in them which explains the challenge of producing only one influenza vaccine
55
What are used to divide influenza viruses into types A, B, and C?
antigenic differences b/w internal structure proteins, nucleocapsid (NP) and matrix (M) proteins
56
Antigenic variation among surface glycoproteins, HA and NA are used to (blank) the viruses
subtype
57
What is the nomenclature system for influenza virus?
type, host origin, geographic origin, strain number, year of isolation, HA and NA subtype
58
```
There are (Blank) subtypes of HA (HA1-HA15) and (blank) subtypes of NA (N1-N9) in many different combinations isolated in birds, animals or humans.
Which types of H and which types of N are found in humans?
```
15
9
H1,2,3,5 and N1 and N2
59
(blank) proteins and (blank) proteins are relatively stable conserved sequences that do not drift as much as glycoproteins.
nucleocapsid proteins and matrix proteins
60
What are susceptible cells?
Cells that viruses can enter but cannot replicate inside
61
What are permissive cells?
cell has everything the virus needs to replicate
62
(blank) on the influenza virus binds to suscpetible cells
HA protein
63
(blank) is the MAJOR antigen which neutralizing (protective) antibodies are directed
HA
64
(blank) is primarily responsibe for the continual evolution of new strains and subsequent influenza epidemics
Variability of HA
65
What does NA do and when does it start doing its job?
facilitates the release of virus particles from infected cell surface during the budding process-> functions at the end of the viral replication cycle
66
(blank) have a selective advantage over parental virus (original virus) in the presence of antibody directed against the original strain.
Antigenic variants
67
Minor antigenic changes are (blank), major changes in HA and NA are termed (blank)
antigenic drift
| antigenic shift
68
What is antigenic drift due to?
accumulation of point mutations in the gene and sequence changes can alter antigenic sites on the glycoprotein
69
Antigenic shift reflects (blank) changes in the sequence of the viral glycoproteins. What is the mechanism for this?
drastic changes
| genetic reassortment b/w human and avian influenza viruses
70
How does influenza virus spread?
from person to person by airborne droplets or by contact with contaminated surfaces
71
What does the influenza virus do to the respiratory epithelium?
How long is the incubation period?
infects them, kills them and spreads to other cells
| -1 to 4 days
72
When is interferon detectable in respiratory secretions?
about 1 day post infection
73
Antibody and cell mediated immunity for influenza is detectable in (blank) weeks
1-2
74
In influenza, cellular destruction is widespread and therefore resistance to (blank) is common.
What ones in particular?
secondary bacterial infections
| -staph, strep, and H. influenzae
75
How is interferon turned on?
double stranded RNA, viral glycoproteins, bacterial LPS
76
What does IFN do?
upregulates the amount of MHC that is displayed, signals for macrophages and neutrophils. Stops viral replication and warns neighboring cells that there is a virus around
77
Routine annual influenza vaccination is recommended for all persons aged (blank)
greater than 6 months
78
What are the three kinds of flu viruses commonly circulating among people today?
Influenza A (H1N1) viruses, Influenza A (H3N2) viruses, and influenza B viruses
79
What rae the vaccine virus strains included in the 2014-2015 trivalent vaccine?
an A/California/7/2009 (H1N1)pdm09-like virus
an A/Texas/50/2012 (H3N2)-like virus
a B/Massachusetts/2/2012-like virus.
B virus (B/Brisbane/60/2008-like virus).
80
What is this:
A 70-year-old women with a history of congestive heart failure is seen in January by her primary care physician with an abrupt onset of fever, cough, and myalgia that requires hospitalization. Two days later, she experiences increasing cough and shortness of breath. Chest X-ray reveals lung infiltrates.
Orthomyxovirus-Influenza virus
81
(blank) is the most common cause of pneumonia and bronchiolitis in INFANTS
RSV
82
Who are susceptible to getting pneumonia with RSV?
neonates, premature infants, infants with cardiopulmonary disease
83
How is RSV transmitted?
via respiratory droplets
84
What does RSV cause in adults?
| In elderly?
common cold and bronchitis
| pneumonia
85
Infants with RSV have pronounced (blank) and ( blank)
cough and expiratory wheezing
86
How do you detect RSV in the respiratory secretions?
Rapid antigen test
87
(blank) is recommended for severely ill hospitalized infants.
How does it work?
Ribavirin
| Stops viral RNA synthesis and viral mRNA capping (guanosine ribonucleic analog)
88
(blank) with a monoclonal antibody directed against the fusion protein of RSV (palivizumab, Synagis) can be used for prophylaxis in premature or immunocompromised infants.
Passive immunization
89
What are the surface spikes on RSV?
fusion proteins
90
What will the fusion proteins on RSV cause?
cells to fuse and form multinucleated giant cells (synctia) (this is why we call it respiratory synctial virus)
91
RSV causes outbreaks every (blank). Where does it occur? Who gets infected with it?
winter
worldwide
virtually everyone has been infected by age of 2-3
92
RSV also causes outbreaks of respiratory infections in hospitalized (blank). Outbreaks can be controlled by (blank)
infants
| hand washing and using gloves
93
When infants and children are exposed to RSV for the first time, 25% to 40% of them have signs or symptoms of (blank or blank)
bronchiolitis or pneumonia
94
A 6-week-old infant is brought to the pediatric clinic in respiratory distress. Physical examination is significant for diffuse expiratory wheezing and mild cyanosis. The chest X-ray is suggestive of bilateral pneumonia. The infant is admitted to the intensive care unit. Nasopharyngeal swab and nasopharyngeal washing are sent for culture and direct examination.
RSV
95
What does parainfluenza virus cause in children?
What does it cause in adults?
How is it transmitted?
croup, laryngitis, bronchiolitis pneumonia in children
- common cold
- respiratory droplets
96
What is the main cause of croup in children younger than 5 years old?
PIV 1 and 2
97
Croup is characterized by a (blank) and (blank)
barking cough and hoarseness
98
Parainfluenza virus also causes a variety of respiratory diseases such as the (blank X 6)
common cold, pharyngitis, laryngitis, otitis media, bronchitis, and pneumonia
99
(blank) is seen in lower respiratory infections in children. Most infections are diagnosed (blank)
PIV 3
| clincally
100
The surface spikes consist of (blank) (blank) and (blank) on parainfluenza virus
HA (hemagglutinin), NA (neuraminidase), F (Fusion proteins)
101
What does the fusion protein do on parainfluenza virus?
mediates the formation of multinucleated giant cells
102
In parainfluenza virus, the (blank and blank) proteins are on the same spike; the F protein is on a (blank) spike
HA and NA
| separate
103
Parainfluenza virus causes and upper and lower respiratory tract disease without (blank)
viremia
104
Antibody to either the HA or the F protein neutralizes (blank). Is there a vaccine or therapy available?
infectivity
| no
105
A 2-year-old child is brought to the emergency department by worried parents because of a barking cough and inspiratory stridor that got worse at night. The present illness began 2 days earlier with a fever, sore throat, rhinorrhea, and mild cough. Finding on examination include a temperature of 102oF, tachypnea, wheezing, and respiratory distress.
croup
