1.3 Respiratory Viruses Flashcards

1
Q
  • family orthomyxoviridae
  • ssRNA, enveloped viruses with a helical nucleocapsid
  • genome of 7-8 segments
  • types A, B, C, D
  • HA, NA, M2
A

influenza viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

in influenze viruses, facilitates attachment to sialic acid rececptor

A

hemagglutinin (HA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

in influenza virus, facilitates release of infectious virus from cells

A

neuraminidase (NA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

in influenza virus, necessary for virus entry

A

M2 protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

influenza pathogenesis?

A

virus deposited on the respiratory tract epithelium, attaches to and penetrates columnar epithelial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

normally prevents attachment of influenza virus to columnar epithelial cells?

A

specific secretory IgA antibodies against hemagglutinin, mucoproteins, and mucociliary apparatus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

key cytokine storm mediators in influenza?

A

IL-6, TNF-alpha, Interferon a/b, IL-1 a/b, IFN-gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q
  • point mutations in antigenic sites reduce or inhibit binding of neutralizing antibodies
  • generally results in local epidemics
  • occurs in influenza A and B
A

antigenic drift

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q
  • a sudden, major change in the antigenic structure of HA and/or NA
  • results in pandemics because the populations don’t have neutralizing antibodies against the new virus
  • occurs only in influenza A
A

antigenic shift

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q
  • two different viruses infect the same cell

- new strains emerge

A

genetic reassortment influenza

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

H1N1 resembles an _____ origin virus, reappeared as Russian flu in 1977

A

avian

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

in influenza immunity, which are the protective antigens of the virus?

A

HA and NA glycoproteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

influenza vaccines are ________ and given ________, the purified virus is split with a detergent and components purified

A

inactivated, intramuscularly

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q
  • enveloped, pleomorphic virions
  • contain non-segmented, (-) ssRNA
  • syncytia inducing viruses
A

paramyxoviruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

includes measles virus, mumps, respiratory syncytial virus, metapneumovirus

A

paramyxovirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

attachment protein of paramyxovirus and mumps?

A

HN protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

attachment protein in measles?

A

H glycoprotein

18
Q

attachment protein in RSV?

A

G glycoprotein

19
Q

all paramyxoviruses have a ________ protein, allows syncytia to form

A

F (fusion)

20
Q

replication of paramyxovirus?

A

fusion of viral and cellular membrane through action of F protein, makes positive transcript, mRNAs translated to protein, assembly and release at plasma membrane

21
Q

paramyxoviruses cause fusion of neighboring cells, mediated by F protein of virus

A

syncytia formation

22
Q

measles rash caused by a ______ response against infected endothelial cells

23
Q

-measles virus infects cells of the ______ tract, then spreads ________

A

respiratory tract, systematically

24
Q

essential to control infection in measles, antibody is not sufficient

A

cell mediated immunity

25
requirements for measles?
cough, coryza, conjunctivitis, temp >101, maculopapular rash >3 days
26
most common complication of measles?
acute otitis media
27
slowly progressing neurodegenerative disease post-measles infection, get cognitive change then motor dysfunction followed by vegetative state
subacute sclerosing panencaphalitis
28
- acute, benign viral parotitis, can cause encephalitis as well as orchitis - only one serotype, man is only reservoir - cell mediated immunity essential, antibody not sufficient to prevent virus spread - immunity is lifelong
mumps virus
29
- major cause of lower respiratory tract infections and hospital visits during infancy and childhood - belongs to pneumovirus and paramyxovirus family
respiratory syncytial virus
30
at risk of severe infection with RSV?
- infants with congenital heart disease - underlying pulmonary disease such as bronchopulmonary dysplasia - immunosuppressed or immunocompromised
31
- ssRNA virus, enveloped, pleomorphic | - 5 serotypes, no antiviral therapy
parainfluenza virus
32
- an enveloped RNA virus, member of the family togaviridae | - RNA of positive polarity, only one serotype, humans the only reservoir
rubella virus
33
in non immune mothers are infected in the first trimester, 80% of neonates affected
rubella virus
34
- initial site of infection the upper respiratory tract, then viremia - immunologic basis for rash - patient infectious from 1 week before rash to 1 week after - maculopapular rash
rubella
35
- infection of fetus may affect all organs, leading to fetal death or premature delivery - 85% affected if during first trimester - triad of cataracts, heart defects, sensorineural loss
congenital rubella syndrome
36
triad of symptoms in congenital rubella syndrome?
cataracts, heart defects, sensorineural deafness
37
what type of vaccine is MMR?
live attenuated
38
two viruses responsible for the common cold?
rhinovirus and coronavirus
39
- small non-enveloped ssRNA virus - belong to picornavirus family - acid labile, greater than 110 serotypes
rhinoviruses
40
ssRNA virus, enveloped, pleomorphic | -can causes SARS and MERS
coronavirus