Vaccinations and Immunisations

Question 1

What are the essential characteristics of vaccines?

Answer 1

• must provide effective protection without risk of causing disease or severe side effects
• protection should be long-lived
• should stimulate correct arm of immune response (antibodies/T cells)
• must be stable for long-term storage/transport
• must be economically affordable for widespread use

Question 2

What are the types of vaccines?

Answer 2

• live
• attenuated
• killed
• extract
• recombinant
• DNA

Question 3

Live vaccines

Answer 3

organisms capable of normal infection and replication. Not used against pathogens that can cause severe disease

Question 4

Attenuated vaccines

Answer 4

organism is live, but ability to replicate and cause disease reduced by chemical treatment or growth-adaptation in non-human cell lines (eg. MMR)

Question 5

Killed vaccines

Answer 5

organism killed by physical/chemical treatment. Incapable of infection/replication but still able to provoke strong immune response (eg. B. pertussis, typhoid)

Question 6

Extract vaccines

Answer 6

materials derived from disrupted or lysed organism (eg. capsular polysaccharides). Used when there is risk of organism surviving inactivation steps (eg. flu, diptheria, tetanus)

Question 7

Recombinant vaccines

Answer 7

genetically engineered to alter critical genes. Often can infect and replicate but does not induce associated disease

Question 8

DNA vaccines

Answer 8

naked DNA injected. Host cells pick up DNA and express pathogen proteins that stimulate immune response

Question 9

What are the safest vaccines?

Answer 9

• live/attenuated
• because they express proteins that stimulate the immune response in a way that most closely resembles normal infection
• safest but not always the most effective

Question 10

What is the main advantage of vaccines?

Answer 10

• herd immunity
• if enough people are vaccinated then the chances of an unprotected person meeting a pathogen becomes small
• allows population to remain essentially resistant

Question 11

Why have vaccination rates fallen?

Answer 11

• herd immunity has made people unaware of the dangers of disease and have stopped getting them
• people are afraid of side effects

Question 12

What does the DTaP/IPV/Hib vaccination protect you against?

Answer 12

• diptheria
• tetanus
• pertussis
• inactivated polio vaccine
• haemophilus
• influenzae type B

Question 13

What does the DTaP/IPV vaccination protect you against?

Answer 13

booster vaccine for:

• diptheria
• tetanus
• pertussis

Question 14

What does the Td/IPV vaccination protect you against

Answer 14

booster vaccine for:

• tetanus
• diptheria
• polio

Question 15

What vaccine is offered to 65 year old individuals and older?

Answer 15

pneumococcal

Question 16

What is the role of dendritic cells in vaccination?

Answer 16

• activate T cells and initiate adaptive immune responses

- express pattern recognition receptors (members of toll-like receptor family)

Question 17

What is the advantage of activation of dendritic cells?

Answer 17

increases the ability of them to capture and process antigen and immunogens and also attract and activate T cells

Question 18

What is the advantage of including CpG in HepB and flu vaccines?

Answer 18

increased abtibody or IFN-y secretion

Question 19

Describe what happens when a dendritic cell meets an antigen?

Answer 19

• encounters antigen in periphery and becomes activated
• migrates to lymph node
• activates T cells to become effector cells