Vaccinology - definitions, components, types of vax, dev't part 1

Question 1

what are the two main means of immunization (2)

Answer 1

1- active
2- passive

Question 2

what is active immunization (1)

Answer 2

making the body actively generate antibodies after vaccination - e.g. the process after any vaccine is given

Question 3

compared to passive imm, how quickly do you get protected, and how long does protection from active immunization last - general terms (1)

Answer 3

takes longer to make antibodies but protection lasts longer

Question 4

what is passive immunization (2)

Answer 4

1- giving the body pre-formed antibodies for immediate but temporary protection against a disease for around 1 month
2- includes trans placental transfer of antibodies from mom to baby (e.g. pertussis…you get Tdap vaccine in pregnancy)

Question 5

why/when is passive immunization useful (2)

Answer 5

1- useful for when there’s isn’t a vaccine available, or vaccine is c/i
2- or if a susceptible individuals has been exposed to an infectious agent and requires immediate protection (e.g. PEP)

Question 6

what are some examples of passive immunization (MVBART) (6)

Answer 6

Ig for:
1- measles
2- varicella
3- hep A
4- hep B
5- rabies
6- tetanus

Question 7

what is immunity (2)

Answer 7

1- protection from an infectious disease
2- if you are immune to a disease, you can be exposed to it without becoming infected

Question 8

what is vaccinology (1)

Answer 8

1- the science of vaccine development and how the immune system responds to vaccines

Question 9

what is a vaccine (1)

Answer 9

1- a product that stimulates a person’s immune system to produce immunity to a specific disease, protecting the person from that disease

Question 10

what are the 5 components of a vaccine (PAAAS) (5)

Answer 10

1- preservatives
2- antigen
3- additive
4- adjuvant
5- stabilizer

Question 11

describe the preservative component of a vaccine and give an example (1 + 1)

Answer 11

1- preservatives: added to prevent fungal or bacterial contamination
2- e.g. thimerosal in multi-dose flu vax vials and hep B vax; e.g. formaldehyde, phenol

Question 12

describe the adjuvant component of a vaccine and give an example (2 + 1)

Answer 12

1- adjuvant: added to enhance immune response to vaccine by extending duration of B and T cell responses
2- work to reduce the amount of antigen in a vaccine dose, and/or reduce the number of total doses needed to gain immunity
3- e.g. Aluminum salts, ASO4 (proprietary)

Question 13

describe the antibiotic component of a vaccine and give an example (2 + 1)

Answer 13

1- antibiotic: residual from the manufacturing process to prevent bacterial contamination of culture cells
2- only trace amounts in vaccines
3- e.g. neomycin, streptomycin, polymyxin B)

Question 14

describe the antigen component of a vaccine and give an example (2 + 1)

Answer 14

1- antigen: derived from disease-causing agent
2- is the component that the body will produce an immune response to (considered foreign by the body)
3- any antigen e.g. rabies virus, influenza virus

Question 15

describe the stabilizer component of a vaccine and give an example (2 + 1)

Answer 15

1- stabilizers (additives): used to preserve potency
2- used to stabilize a vaccine against heat or freeze-dried conditions, against pH variation, against protein/carbohydrate aggregation or hydrolysis
3- e.g. MgSO4; gelatin; human serum albumin

Question 16

what are the determinants of vaccine response - PACVHOTRI (9)

Answer 16

1- presence of adjuvant
2- antigen dose
3- carrier protein
4- vaccine type
5- host factors
6- other (route)
7- timing between doses
8- recipient age
9- immune system status

Question 17

describe the ‘antigen dose’ determinant of vaccine response (1)

Answer 17

Antigen dose - higher dose (to a threshold) means higher immune response

Question 18

describe the ‘conjugate/carrier protein’ determinant of vaccine response (1)

Answer 18

Carrier protein - antigen conjugated to a carrier protein that’s easily recognized by the body will lead to more robust immune response

Question 19

describe the ‘vaccine type’ determinant of vaccine response (1)

Answer 19

Vaccine type - live attenuated has greater response than inactivated vaccine

Question 20

describe the ‘host factors’ determinant of vaccine response (1)

Answer 20

Host factors - age, sex, comorbidities

Question 21

describe the ‘timing between doses’ determinant of vaccine response (1)

Answer 21

Timing between doses - need sufficient time to build successive waves of B cell response to go from primary response (slow production of antibodies) to secondary response (rapid production of antibodies since memory B cells recognize antigen)

Question 22

describe the ‘recipient age’ determinant of vaccine response (2)

Answer 22

1- recipient age: extremes of age have lower immune responses from vaccination
2- younger age = less mature immune system, less response; old age = lower response as well

Question 23

describe the ‘immune system status’ determinant of vaccine response (1)

Answer 23

Immune system status: immunocompromised people have limited immune response

Question 24

what are the qualities of an ideal vaccine “farmer Ed’s easy ass - Easy ASS E-I-E-E-D (5 + 4)

Answer 24

1- easy to administer
2- affordable
3- safe
4- stable
5- effective
5a- immunogenicity
5b- efficacy
5c- effectiveness
5d- duration of protection

Question 25

describe the 'easy to administer' quality of an ideal vaccine (2)

Answer 25

1- Oral and intranasal = easier to administer than injectable 2- you only administer the minimum number of doses required

Question 26

describe the 'affordable' quality of an ideal vaccine (2)

Answer 26

1- Older vaccines cost only a few dollars per dose, while newer vaccines can cost $60/dose 2- Competition brings the price down

Question 27

describe the 'safe' quality of an ideal vaccine (3)

Answer 27

1- Common side effects are mild, serious side effects are rare 2- Does not cause disease 3- disease not transmissible to others

Question 28

describe the 'stable' quality of an ideal vaccine (2)

Answer 28

1- Temperature (ideally doesn’t require cold-chain) 2- Long shelf-life

Question 29

describe the 'effective' quality of an ideal vaccine (4)

Answer 29

1- Immunogenicity: induces antibodies in individuals 2- Efficacy: reduces disease in clinical trials 3- Effectiveness: reduces disease in real-world populations 4- Duration of protection: need for boosters is limited (no waning immunity)

Question 30

what are the two main categories of vaccine types (2)

Answer 30

1- live-attenuated (Contain whole, weakened bacteria or virus) 2- non-live

Question 31

what are pros of live-attenuated vaccines (2)

Answer 31

1- Strong immune response (immunity similar to natural infection) 2- Single dose may be sufficient

Question 32

what are cons of live-attenuated vaccines (3)

Answer 32

1- Rare potential to revert to virulence (e.g., polio) 2- Contraindicated in pregnancy and immunocompromised people 3- Possible interaction with other live virus vaccines (4 weeks between doses)

Question 33

what are examples of live vaccines - BYMR VPoL (7)

Answer 33

1- BCG 2- Yellow fever 3- MMR 4- rotavirus 5- varicella 6- oral polio 7- live attenuated influenza

Question 34

what are the subtypes of non-live vaccines - SIT NV (5)

Answer 34

1- subunit-based 2- inactivated antigen 3- toxoid 4- nucleic acid 5- viral vector

Question 35

what are the sub-subtypes of subunit-based vaccines - PCP (3)

Answer 35

1- protein-subunit 2- conjugate subunit 3- polysaccharide subunit

Question 36

what is a protein-subunit vaccine (1)

Answer 36

1- it Presents an antigen to the immune system using an isolated protein of the pathogen

Question 37

what are pros of protein subunit vaccines (1)

Answer 37

1- No live components so no risk of causing disease

Question 38

what are cons of protein subunit vaccines (1)

Answer 38

1- If denatured, isolated proteins may bind to different antibodies than the protein of the pathogen

Question 39

what are examples of protein subunit vaccines (1)

Answer 39

1- acellular pertussis (aP)

Question 40

what is a conjugate subunit vaccine (1)

Answer 40

1- also uses the bacterial polysaccharide capsule, but adds a conjugated carrier protein

Question 41

what are pros of conjugate vaccines (2)

Answer 41

1- Can induce long-term immunity 2- induce immune response in infants

Question 42

what are cons of conjugate vaccines (1)

Answer 42

1- more difficult to manufacture

Question 43

what are some examples of conjugate vaccines (2)

Answer 43

1- Haemophilus influenzae type B (Hib) vaccine 2- Pneumococcal conjugate vaccine

Question 44

what is a polysaccharide subunit vaccine (1) How does a bacteria’s polysaccharide capsule relate to infecting young children (1)

Answer 44

1- uses the bacterial polysaccharide capsule as the antigen 2- some bacteria use a polysaccharide capsule to evade the immune system (this is particularly effective in young children)

Question 45

What are some examples of encapsulated bacteria (7) - SHiNE SaSK

Answer 45

Streptococcus pneumonia Hib (haemophilus influenzae) Neisseria meningitidis E Coli Salmonella GB**S** Klebsiella

Question 46

what are pros of polysaccharide vaccines (2)

Answer 46

1- No live components so no risk of causing disease 2- Induce short- term immunity

Question 47

what are cons of polysaccharide vaccines (2)

Answer 47

1- Molecules are small and often not very immunogenic 2- May not induce long-term/durable immunity

Question 48

what are examples of polysaccharide vaccines (2)

Answer 48

1- Meningococcal polysaccharide A,C,Y, W- 135 vaccine 2- Pneumococcal polysaccharide vaccines

Question 49

what is an inactivated antigen vaccine (1)

Answer 49

1- Contains whole or parts of an inactivated agent

Question 50

what are pros of inactivated antigen vaccines (3)

Answer 50

1- Stable 2- Unable to cause the infection 3- Can use in pregnancy

Question 51

what are cons of inactivated antigen vaccines (3)

Answer 51

1- May require several doses/boosters 2- Adjuvant may be needed 3- Shorter lasting immunity

Question 52

what are some examples of inactivated antigen vaccines - HaRIP (4)

Answer 52

1- hep A 2- rabies 3- influenza (non-live) 4- inactivated polio

Question 53

what is a toxoid vaccine (1)

Answer 53

1- Uses a weakened toxin made by the agent that causes disease

Question 54

what is a pro of toxoid vaccine (similar to general non-live vaccine pro) (1)

Answer 54

1- cannot cause disease

Question 55

what are cons of toxoid vaccine (similar to general non-live vaccine cons) (2)

Answer 55

1- May require several doses/boosters 2- Adjuvant may be needed

Question 56

what are examples of toxoid vaccine (1)

Answer 56

1- DTaP vaccine contains diphtheria and tetanus toxoids

Question 57

what are sub-subtypes of nucleic acid vaccines - MR (2)

Answer 57

1- mRNA 2- recombinant

Question 58

what is an mRNA vaccine (1)

Answer 58

1- uses viral mRNA to make proteins in a host body in order to trigger an immune response

Question 59

what are pros of mRNA vaccines (1)

Answer 59

1- Shorter manufacturing times

Question 60

what are cons of mRNA vaccines (1)

Answer 60

1- Require specialized cold shipping/storage conditions at -80 degC

Question 61

what is an example of mRNA vaccine (1)

Answer 61

1- COVID-19 Vaccines

Question 62

what is a recombinant vaccine (1)

Answer 62

1- allow vaccine proteins to be expressed by alternative cell types in controlled settings, including insect, plant, yeast, and mammalian cells (instead of eggs, for example) - these proteins are then used as antigens in vaccine

Question 63

what are pros of recombinant vaccines (1)

Answer 63

1- No live components so no risk of causing disease

Question 64

what are the cons of recombinant vaccines - general like non-live (1)

Answer 64

1- May not induce long-term immunity

Question 65

what are examples of recombinant vaccines (2) - HH

Answer 65

1- Hepatitis B vaccine 2- HPV vaccine

Question 66

what is a viral vector vaccine (1)

Answer 66

1- Use modified version of different, 'harmless' virus as vector for delivering antigen to host cells

Question 67

what are pros of vector vaccines (1)

Answer 67

1- elicit strong immune response

Question 68

what are cons of vector vaccines (different con to general non-live vaccines) (1)

Answer 68

1- Previous exposure to vector virus may reduce effectiveness of vaccine

Question 69

what are examples of vector vaccines (1)

Answer 69

1- COVID-19 vaccine with adenovirus vector

Question 70

who are key stakeholders in vaccine development & approval in Canada - HFN CPCP (7)

Answer 70

1- health canada - BRDD - biologics and radiopharmaceutical drugs directorate (second in process) 2- food and drugs act (first in process) 3- NACI - national advisory committee on immunization 4- CIC - canadian immunization committee 5- PHAC - public health agency of canada 6- CATMAT - committee to advise on tropical medicine and travel 7- PT - provinces and territories

Question 71

describe 'health canada' as a key stakeholder for vaccine dev't and approval in canada (3)

Answer 71

1- federal authority that reviews the clinical and manufacturing information of vaccine submissions 2- authorizes sale of vaccines that are safe, effective, of high quality, and whose benefits outweigh the risks 3- Also monitors vaccine safety and effectiveness

Question 72

describe 'food and drugs act' as a key stakeholder for vaccine dev't and approval in canada (2)

Answer 72

1- categorizes vaccines as biologic drugs 2- Requires special expertise and procedures for their manufacture, control, and regulation

Question 73

describe 'NACI' as a key stakeholder for vaccine dev't and approval in canada (3)

Answer 73

1- makes expert and evidence-based recommendations on vaccine use, strategy, research, programs 2- uses AFEEE for evaluating programs - acceptability, feasibility, ethics, equity, economics) 3- produces the Canadian immunization guide (CIG)

Question 74

describe 'CIC' as a key stakeholder for vaccine dev't and approval in canada (1)

Answer 74

1- reps from FPT who provide recommendations to Ministries of Health on vaccine program planning and policies, through PH network council

Question 75

what are the working groups of CIC (4)

Answer 75

1- VSWG: vaccine safety 2- VVWG: vaccine vigilance 3- CIRC: CAN imm registry & coverage 4- NISWG: national immunization strategy working group (determines priorities, goals, targets)

Question 76

describe 'PHAC' as a key stakeholder for vaccine dev't and approval in canada (4)

Answer 76

1- Monitors vaccine safety via CAEFISS and IMPACT (peds) 2- Bulk procurement of publicly funded vaccines 3- Population vaccine coverage assessment 4- engages in imms awareness/promotion

Question 77

describe 'CATMAT' as a key stakeholder for vaccine dev't and approval in canada (2)

Answer 77

1- makes Recommendations re: tropical infectious diseases and health risks with international travel 2- generates travel health notices to help protect all Canadians upon travellers' return to Canada

Question 78

what are the levels of CATMAT travel health notices? (4)

Answer 78

1- Practice Usual Precautions (hand hygiene) 2- Practice Enhanced Precautions (vaccines if local outbreak) 3- Avoid non-essential travel (if large outbreak) 4- Avoid all travel (there is risk of bringing back disease to Canada despite precautions)

Question 79

describe 'PT' as a key stakeholder for vaccine dev't and approval in canada (5)

Answer 79

1- deliver immunization programs 2- set the imms schedules based on jurisdictional context and NACI guidance 3- determine who/what circumstances are the vaccines publicly funded 4- purchase vaccines for publicly funded programs 5- maintain vaccine registries

Question 80

what are the steps in vaccine development (6)

Answer 80

1- register 2- preclinical phase 3- phase 1 4- phase 2 5- phase 3 6- phase 4

Question 81

describe the 'register' phase of the vaccine development process (1)

Answer 81

1- researchers/manufacturers need to register/submit an application for a clinical trial with BRDD at Health canada

Question 82

describe the 'preclinical' phase of the vaccine development process (2)

Answer 82

lab/animal testing to see: 1- whether expected immune response is provoked; 2- whether there are any toxicities that would prevent use of candidate vaccine in humans

Question 83

describe the 'phase 1' phase of the vaccine development process (3)

Answer 83

1- 10s of volunteers 2- is the vaccine safe? 3- does it provoke an immune response?

Question 84

describe the 'phase 2' phase of the vaccine development process (3)

Answer 84

1- 100s of volunteers (target vaccinee group) 2- continue to check safety 3- determine best dose/schedule

Question 85

describe the 'phase 3' phase of the vaccine development process (4)

Answer 85

1- 1000s of volunteers (variable group) 2- safety in larger groups 3- efficacy - does vaccine prevent disease 4- can submit to licensing after phase 3

Question 86

describe the 'phase 4' phase of the vaccine development process (3)

Answer 86

1- post-licensing surveillance 2- assess real-world effectiveness 3- look for rare or unexpected adverse events