Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Foundations Of Medicine > 11.6 Viral Transmission and Pathogenesis > Flashcards

11.6 Viral Transmission and Pathogenesis Flashcards

1
Q

Describe direct virus transmission. Through what can it occur?

A
  • Occurs through direct body contact with tissues or fluids of infected individual
  • Can occur through mucous membranes (e.g. eyes/mouth) and skin/wounds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe two mechanisms of indirect virus transmission

A
  • Fomite transmission
  • Vector mediated transmission (e.g. mosquitos)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe three kinds of transmissions of viruses between/within humans and other animals

A
  • Enzootic (Within one animal species)
  • Epizootic (between multiple animal species)
  • Zoonotic (from animals to humans via any means)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe different modes of viral transmission across mucosal surfaces

A
  • Respiratory (airborne)
  • Enteric (oral)
  • Sexual transmission
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe different modes of viral transmission that involve skin penetration

A
  • Bloodborne
  • Vector-borne
  • Cuts, scrapes, bites, needles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is viraemia?

A

Virus existing in blood

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

What does it mean that viruses are obligate intracelllular parasites?

A

They must enter a host cell in order to replicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the only situation in which the genome of a virus can serve its function?

A

Inside a living cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are four important aspects of viral pathogenesis?

A
  1. Transmission
  2. Viral Replication (effect on infected cells?)
  3. Spread within the body (areas?)
  4. Evasion of host defense systems
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Transient vs persistent infection

A

Transient: successful clearance
Persistent: unsuccessful clearance

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

What is a single viral particle called?

A

Virion

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

List five possible effects of viral infection at the cellular level

A
  1. Cytopathic effect (cell death/cytoskeletal changes)
  2. Giant cell formation
  3. Malignant transformation
  4. Inclusion bodies
  5. No change
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the opposite of a localised infection?

A

Systemic infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What factors can influence the effectiveness of an antiviral immune response?

A
  • Rate of virus replication & antigen presentation
  • Size of dose of virus
  • Route of infection/host age
  • Ability of virus to evade the immune system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Which two concepts underlie the clinical presentation of viral infection?

A
  • Effects of viral replication on host
  • Symptoms caused by the antiviral immune response itself
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the four classifications of viral infections in terms of permutations?

A
  • Transient localised
  • Transient systemic
  • Persistent localised
  • Persistent systemic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

List five different regions in which infection can occur

A
  • Respiratory tract
  • Gastrointestinal tract
  • Liver
  • Nervous system
  • Skin
18
Q

Give an example of a viral respiratory infection

A

Influenza

19
Q

Give an example of a viral GI infection

A

Gastroenteritis

20
Q

Give an example of a viral Liver infection

A

Hep A/B/C

21
Q

Give an example of a viral nervous infection

A

Encephalitis

22
Q

Give an example of a viral skin infection

A

Chickenpox

23
Q

Effect of tumour necrosis factor alpha

A
  • Promotes systemic inflammation
  • Inflammatory chemokines production and leukocyte recruitment
24
Q

Effect of interleukin 1 beta

A
  • Mediates inflammatory response
  • Promotes inflammatory chemokine response and leukocyte recruitment
25
Q

Effects of type 1 interferon

A
  • Induces cellular resistance to viral infection
  • Inhibits viral replication/dissemination
26
Q

What are PAMPs?

A

Pathogen associated molecular patterns

27
Q

What are DAMPs?

A

Damage associated molecular patterns

28
Q

What receptors detect viral infection in the innate immune system?

A

Pattern recognition receptors

29
Q

Which antigen presenting cells in the innate immune response detect viral infection?

A
  • Dendritic cells
  • Macrophages
30
Q

What can PRRs detect?

A

PAMPs and DAMPs

31
Q

What are the two types of PRRs?

A
  • Cytosolic receptors
  • Toll-like receptors
32
Q

What do cytosolic recptors detect?

A

DNA and RNA in the cell

33
Q

Where are cytosolic receptors present?

A

In the cytoplasm

34
Q

How can nucleic acid be a PAMP if our own cells have DNA and RNA?

A
  1. Viral RNAs lack the methyl cap on the 5’ end, which our own cells have. Therefore, such RNA is detected as a PAMP, and an immune response is mounted.
  2. Presence of dsRNA in cytoplasm due to genomic replication (doesn’t usually occur)
  3. Presence of dsDNA in cytoplasm
35
Q

Where are TLRs located? How does this influence the importance of various cells?

A
  • Located in endosome
  • Makes the role of phagocytes very important, as these form endosomes
36
Q

What does TLR3 detect?

A

dsRNA

37
Q

What do TLR7/8 detect?

A

ssRNA

38
Q

What do TLR9 detect?

A

Unmethylated CpG-DNA

39
Q

What does “pyrogenic” mean?

A

Causing fever

40
Q

What are the three outcomes of interferon type 1?

A
  • mRNA degradation
  • Inhibition of transcription
  • Inhibition of translation
41
Q

What are some common clinical symptoms of viral infection, and what causes them?

A
  • Fever
  • Tiredness
  • Muscle ache
    Caused by host antiviral response

Foundations Of Medicine (98 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions