Brainscape's Knowledge GenomeTM

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


See full index

Extra > vaccin > Flashcards

vaccin Flashcards

1
Q

A vaccine is

A

Something that stimulates the immune system, without causing serious harm or side effects

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

Aim of immunisation

A

to provoke immunological memory to protect individual against a particular pathogen if they later encounter it

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

Features of an ideal vaccine

A 
Completely safe
Easy to administer
Single dose, needle-free
Cheap
Stable
Active against all variants
Life-long protection
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what are the single most cost-effective tool we have for improving health

A

Vaccines

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

3 areas that vaccine work towards

A

Prevention of Entry
Killing infected cells
Boosting Immune Response

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

2 methods of Prevention of Entry

A

Antibody: Blocks Entry by binding onto the virus and nuetrilising
Macrophage: Engulfs Pathogen by opsinisation

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

how do they boost Immune Response

A

antigens recognised by CD4 T cells
programmed to boost other areas of immune response e.g. train CD8 cells to kill infected cells or make with b cells to make better antibodies

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

what is R0

A

Basic reproduction number

The number of cases one case generates on average over the course of their infectious period

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

what happens if R0 < 1

A

the infection will die out in the long run

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

what happens if If R0 > 1

A

the infection will be able to spread in a population.

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

how do vaccine reduce r0

A

immunise people, fewer people become infected after first wave

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

what Sustained

transmission

A

Transmitting

case infect Susceptible and they infect other people who infect other people ect

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

how do vaccine cause the Transmission terminated

A

Transmitting people meet immune people who won’t pass it on- herd immunity

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

what are the forms an antigen is in in a vaccine

A 
Inactivated Protein e.g. Tetanus toxoid
Recombinant protein e.g. Hep B
Live Attenuated Pathogen e.g. Polio/ BCG
Dead Pathogen e.g. Split Flu vaccine
Carbohydrate e.g. 
S. pneumoniae
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what else is in a vaccine

A

Adjuvant, normally alum, sometimes something proprietary
Stabilising stuff (e.g. Buffers – PBS)
Water

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

what are Inactivated Toxoid Vaccines

A

Chemically inactivated form of toxin

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

how do they work

A

Induces antibody, (antibody blocks the toxin from binding the nerves in tenus)

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

Advantages

A

Cheap, well characterised, safe, in use for many decades

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

Disadvantages

A

Requires good understanding of biology of infection, not all organisms encode toxins.

20
Q

how do the Recombinant Protein Vaccines work

A

induces classic neutralising antibodies

21
Q

what is a Recombinant Protein Vaccine

A

recombinant protein from pathogen

22
Q

advantages

A

Pure, safe

23
Q

disadvantage

A

Relatively expensive, not very immunogenic, has not proved to be answer to all pathogens

24
Q

difference between recombinat protien vaccien and Inactivated Toxoid Vaccines

A

Recombinant Protein Vaccines are made differently

isolated gene from one organism and moved to another organism

25
Q

recombinant protein vaccine and Inactivated Toxoid Vaccines work well against what

A

protein antigens

26
Q

what is the problem with bacterial coats

A

Bacterial often have a capsule
This is made of polysaccharide
Which is not very good at inducing a B cell response (it is a T independent antigen)

27
Q

how do Conjugate Vaccines

A

Polysaccharide coat component is coupled to an immunogenic “carrier” protein
t cell recognise the protein part and the b cells recognise the sugar part of the protein allowing them to communicate
Protein enlists CD4 help to boost B cell response to the polysaccharide
e they connect (or conjugate) the
polysaccharides to antigens that the immune system responds to
very well. This linkage helps the immature immune system react to
the coating and develop an immune response

28
Q

advantages

A

Improves immunogenicity, highly effective at controlling bacterial infection

29
Q

disadvantages

A

Cost
carrier protein interference,
very strain specific,
polysaccharide alone is poorly immunogenic

30
Q

Dead Pathogen Vaccines differnce from everyother vaccine

A

Rather than using a single antigen, it is chemically killed pathogen

31
Q

how

A

Induces antibody and T cell responses

32
Q

advtg

A

Leaves antigenic components intact and in context of other antigen. Immunogenic because of the inclusion of other components. Cheap. Quick.

33
Q

Disadvantages

A

Fixing/ killing can alter chemical structure of antigen.
Quite “dirty”.
Requires the capacity to grow the pathogen
Vaccine induced pathogenicity a risk.
Risk of contamination with live pathogen (Polio), not happened since 1953

34
Q

Live Attenuated Vaccines

A

similar looking pathogen but doesn’t cause infection

Pathogens are attenuated by serial passage. This leads to a loss of virulence factors.

35
Q

how it works

A

Because they replicate in situ they trigger the innate response and boost the immune response

36
Q

Advantages

A

Induce a strong immune response. Can induce a local immune response in the site where infection might occur

37
Q

Disadvantages

A

Can revert to virulence
Can infect immunocompromised
Attenuation may lose key antigens
Can be competed out by other infections.

38
Q

Adjuvants

A

boost immune response
induce ‘danger signals’ that activate dendritic cells to present antigen to T cells
Part of licensing the response
Adjuvant stimulates the DC
DC uptakes antigen and moves to Lymph node
Upregulates stimulatory signalling and cytokines

39
Q

definition of adjuvant

A

Substances used in combination with a specific antigen that produced a more robust immune response than the antigen alone.

40
Q

Why do we need New Vaccines?

A 
Changing  (aging) Demographics 
Changing Environment 
New Diseases
Old Diseases we still can’t fix
Antibiotic Resistance
41
Q

barriers to future vaccine

A

Scientific Challenges
Injection Safety
Logistics/ Cold Chain (difficulty accessing vaccine)
Development Issues (Time, Cost)
Cost of the product
Public expectation of risk-free vaccines
High Variation of the target organism

42
Q

High Variation of the target organism

A

Virus mutates and evolves

a wide range of antigens

43
Q

serotype

A

one viral strain recognised by one family of antibodies

44
Q

phases of clinical trials

A

p1) drug approved for testing humans
p2) safety and efficacy studies
p3) regulatory agencies review/approval.

45
Q

how vaccine are introduced

A

Recommendations for vaccine policy (JCVI)
Vaccine policy decisions (DH)
Licensing of vaccine(MHRA)
Purchase of vaccine
Control of vaccine (including batch release) (NIBSC)
Post licensure assessment and changes
PHE/ JCVI (Epidemiology, assessment, trials)

46
Q

what are scheduling considertaions

A 
Aim
Need
Scheduling with other vaccines
Availability
Cost
Population accessibility
Cultural attitudes and practices
Facilities available for delivery
47
Q

The issue is sometimes when proteins are synthesised, they may fold differently which means the vaccine would be ineffective.

A

The issue is sometimes when proteins are synthesised, they may fold differently which means the vaccine would be ineffective.

Extra (45 decks)

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