Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > M30- Influenza > Flashcards

M30- Influenza Flashcards

1
Q

What is the largest burden on healthcare?

A

Influenza

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

what do many dental procedures have the potential to generate and what is the significance of this?

A

potential to generate aerosols so risk assessment and effective risk-management actions must be taken to avoid aerosol exposure

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

what should remain available throughout a pandemic?

A

Emergency dental care should remain available throughout a pandemic, although non- urgent services may be reduced if there are shortages of staff and specialist consumables

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

why is emergency dental care important in a pandemic?

A

there may be opportunities to use the assessment and treatment skills of dental practitioners or other health professionals to support the wider delivery of healthcare in a pandemic

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

Name some viral respiratory infections.

A
  • Respiratory syncytial virus (RSV)
  • Rhinovirus (100+ serotypes)
  • Parainfluenza (1-4)
  • Human metapneumovirus
  • Coronaviruses (4 types)
  • Adenoviruses
  • Enteroviruses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name 2 severe viral infections.

A
  • Severe Acute Respiratory Syndrome (SARS)

* Middle Eastern Respiratory Syndrome (MERS)

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

Where does SARS and MERS originate from?

A

Transmission between animal and human

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

what are the two types of flu?

A

Type A and B

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

what percentages of young and old develop the flu?

A

5% adults and 20% of children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

when are the death rates high in relation to flu?

A

secondary infections after having the flu

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

What populations does flu cause the most deaths?

A

elderly and young

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

Why is flu considered seasonal?

A

seasonal temperate climates (temperature, more cases in winter )

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

Which type of flu has a pandemic threat?

A

Type A

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

Describe the clinical presentation of the flu.

A
  • Droplet infection
  • Incubation period 48 hours (24-96)
  • Abrupt onset
  • High Fever, headache, photophobia, cough, shivering, muscle aches, malaise.
  • Inflammation of upper respiratory tract & trachea
  • Weakness & fatigue persists (weeks) – depression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

In what time do acute symptoms resolve?

A

7-10 days (biphasic)

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

what flu is more severe?

A

Flu A is more severe than flu B

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

why is flu hard to treat?

A

abrupt onset

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

where are the principal sites of viral replication in the respiratory tract?

A

Trachea, bronchi & pulmonary alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

when does the damage to respiratory tract and inflammatory response peak?

20
Q

what is the acute phase to the respiratory tract?

A

Desquamation of epithelium of trachea & bronchi

– Reports that in areas only basal layer of cells remain

21
Q

what occurs to the respiratory tract after the acute phase?

A

Edema & congestion of submucosa

– Desquamation of epithelial cells

22
Q

what happens to the respiratory tract in the later stages?

A

Later stages mononuclear inflammatory cells observed, initially no neutrophils detected

23
Q

what type of secondary infection occurs?

24
Q

What is the mortality of the flu?

A

• General figure of 600 deaths due to complications of flu annually in UK
– Infection extends to lower respiratory tract
– Hemorrhagic bronchitis to pulmonary edema associated with death in 48 hours
– Infants & elderly
– Chronic pulmonary or cardiac disease
– Diabetics

25
Q

what are the different types of influenza?

A

A , B and C

26
Q

what components make up the flu virus?

A
  • Enveloped virus
  • Segmented genome (7-8) – Each encapsulated by nucleoprotein
  • ssRNA
27
Q

where is the flu virus grown?

A

in embryonated hens eggs

28
Q

what flu has the widest range of hosts?

A

Type A

-Humans/mammals/birds

29
Q

what is a major component of the flu virus?

30
Q

What is significant about the segmented genome of the flu virus?

A

– 8 gene sequences encoding for at least one protein
– RNA polymerase has no proof reading capacity
– High mutation rate 1-8 x 10-3 substitutions per year
– Amino acid changes in antigenic portions of surface proteins key to evolution

31
Q

what structure of the flu binds the cell surface?

A

Heamagglutinin (HA)

32
Q

what structure of the flu facilitates exit?

A

Neuraminidase (NA)

33
Q

what are N and H targets for?

A

immune response

34
Q

what do the different types of flu affect?

A

All infect birds (some pigs and horses)

35
Q

what is important in the pandemics of influenza?

A

zoonotic element ( i.e. bird flu & swine flu avian flu in aquatic birds likely to be key reservoir)

36
Q

why effect do animal hosts have?

A

Increase antigenic drift

37
Q

what was the mortality rate in 1918-1920 for influenza?

38
Q

what is antigenic drift?

A

Drift (A & B) - minor changes in amino acids on surface structure changes antigenicity
-Allows escape of a virus from collective immunity

39
Q

What is antigenic shift?

A

• Shift (A only) entirely new H or N combinations

– Re-assortment between distinct HA types

40
Q

What population was mostly affected in the 1918 pandemic influenza?

A

20-40 year olds most severely impacted

41
Q

why were 20-40 year affected in 1918?

A
  • Inflammatory response proposed as key

* Cytokine storm

42
Q

Describe the cytosine storm of the pandemic influenza.

A

– Virus infects pnemocytes
– Macrophages activated
– Peptides on surface of macrophage activate T lymphocytes
– Pro-inflammatory chemokines & cytokines released
– Dilation of blood vessels, increased permeability & drop in blood pressure

43
Q

Describe the vaccines of flu.

A
  • Strains circulating monitored worldwide
  • Takes 6 months to produce vaccine
  • Three strains (two type A & one B)
  • Grown in hens eggs & inactivated
  • Now tissue culture grown
  • Attenuated live vaccines – young & healthy
  • Target at-risk groups
  • Annual vaccination
44
Q

Describe the antiviral drugs that treats Flu A only.

A

• Amantadine (Flu A only)

  • M2 component of FluA
  • Allows acidification of virus interior
  • Removal of ribonucleoproteins key step in genome becoming active
  • Blocks M2 ion channel
45
Q

Describe the antiviral drug that treats Flu A and B.

A

• Zanamivir

  • neuraminidase inhibitor, binds to active site
  • interfered with escape from host cell
  • take at onset of symptoms & maybe reduce development by 12% at best & concerns abourt resistance
  • Inhalation, studies on IV delivery
46
Q

Describe the use of the antiviral drug Oseltamivir.

A
  • Oral : neuraminidase inhibitor
  • Can be used prophylactically (> 12 yrs old)
  • Must be given within 48 hrs of symptoms Tend to reduce disease by 1-2 days
47
Q

Summary slide.

A 
• Viral respiratory diseases & dentistry
• Awareness of SARS & MERS
• Influenza, structure H & N classification
• TypeA&B,Cmild
• Seasonal flu & Pandemic flu
• Symptoms & risks
• Prevention & treatment
– Vaccines
– Anti-viral
– Animal/Bird threat

Microbiology (30 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions