5.6- VACCINATION

Question 1

What is immunity?

Answer 1

ability of organism to resist infection

Question 2

What two forms does immunity take?

Answer 2

passive immunity

active immunity

Question 3

What is passive immunity produced by?

Answer 3

introduction of antibodies into individuals from outside source

Question 4

What is not necessary to induce immunity? (passive immunity)

Answer 4

no direct contact with pathogen or its antigen

Question 5

How quick is immunity acquired? (passive immunity)

Answer 5

immediately

Question 6

What happens as the antibodies are not being produced by the individual themselves? (passive immunity)

Answer 6

antibodies not replaced when they’re broken down, non memory cells formed so there’s no lasting immunity

Question 7

Examples of passive immunity?

Answer 7

anti-venom given to victims of snake bites + immunity acquired by fetus when antibodies pass across placenta from mother

Question 8

What is active immunity produced by?

Answer 8

stimulating production of antibodies by individuals’ own immune system

Question 9

What is necessary in active immunity?

Answer 9

direct contact with pathogen or its antigen

Question 10

How quick is immunity acquired? (active immunity)

Answer 10

immunity takes time to develop

Question 11

How long does active immunity generally last?

Answer 11

generally long-lasting

Question 12

What is the two types of active immunity?

Answer 12

natural active immunity

artificial active immunity

Question 13

What does natural active immunity result from?

Answer 13

individual becoming infected with disease under normal circumstances

Question 14

What does the body produce its own of in natural active immunity?

Answer 14

own antibodies + may continue to do so for many years

Question 15

What does artificial active immunity form the basis of?

Answer 15

vaccination (immunisation)

Question 16

What does artificial active immunity involve?

Answer 16

inducing immune response in individual, without them suffering symptoms of disease

Question 17

What is vaccination the introduction of?

Answer 17

appropriate disease antigens into body, either by injection or by mouth

Question 18

What is the intention of vaccination?

Answer 18

stimulate immune response against particular disease

Question 19

What is the material introduced in vaccination called?

Answer 19

vaccine

Question 20

What does a vaccine contain?

Answer 20

one or more types of antigen from the pathogen

Question 21

What do the antigens in the vaccine do?

Answer 21

stimulate immune response

Question 22

What is the immune response stimulated by the antigen in the vaccine like?

Answer 22

response slight as only a small amount of antigen has been introduced

Question 23

What is the crucial factor from a vaccination?

Answer 23

memory cells produced

Question 24

Why is memory cells being produced from vaccination crucial?

Answer 24

these remain in blood + allow greater and more immediate response to future infection with pathogen

Question 25

What is the result of vaccination?

Answer 25

rapid production of antibodies + new infection rapidly overcome before it can cause any harm and with few, if any, symptoms

Question 26

What vaccination is carried out on a large scale, what does it provide?

Answer 26

protection against disease not only for individuals but also for whole populations

Question 27

What sort of measure is vaccination used as?

Answer 27

precautionary measure to prevent individuals contracting disease

Question 28

What are the factors that the success of a vaccination programme is dependent on? (economically)

Answer 28

economically available in sufficient quantities to immunise most of vulnerable population

Question 29

What are the factors that the success of a vaccination programme is dependent on? (side-effects)

Answer 29

must be few side effects if any | unpleasant side effects may discourage individuals in population from being vaccinated

Question 30

What are the factors that the success of a vaccination programme is dependent on? (producing, storing + transporting)

Answer 30

means of producing, storing + transporting vaccine must be available usually involves technologically advanced equipment, hygienic conditions + refrigerated transport

Question 31

What are the factors that the success of a vaccination programme is dependent on? (administering)

Answer 31

must be means of administering vaccine properly at appropriate time involves training staff with appropriate skills at different centres throughout population

Question 32

What are the factors that the success of a vaccination programme is dependent on? (population)

Answer 32

must be able to vaccinate vast majority of vulnerable population to produce herd immunity

Question 33

When does herd immunity arise?

Answer 33

when sufficiently large proportion of population has been vaccinated to make it difficult for pathogen to spread within population

Question 34

What is the concept of herd immunity based on?

Answer 34

idea that pathogens passed from individual to individual when in close contact

Question 35

When the vast majority of the population is immune, what does this mean?

Answer 35

highly improbable that susceptible individual will come in contact with infected person

Question 36

What does it mean for people who are not immune when the vast majority of the population is immune?

Answer 36

they're still protected

Question 37

Why is herd immunity important?

Answer 37

as it's never possible to vaccinate everyone in a large population

Question 38

Who are not vaccinated?

Answer 38

babies and very young children

Question 39

Why are babies and very young children not vaccinated?

Answer 39

as their immune system not yet fully functional

Question 40

Who should not be vaccinated as it can be dangerous?

Answer 40

those who are ill or have compromised immune systems

Question 41

What percentage of the population must be vaccinated to achieve herd immunity?

Answer 41

different for each disease

Question 42

How should vaccination be carried out to achieve herd immunity?

Answer 42

best carried out at one time

Question 43

What does it mean for the vaccination to be carried out at one time?

Answer 43

very few individuals in population with disease + transmission of pathogen interrupted

Question 44

Reasons as to why even if criteria for successful vaccination met, can still prove extremely difficult to eradicate disease? (certain individuals)

Answer 44

vaccination fails to induce immunity in certain individuals e.g. people with defective immune system

Question 45

Reasons as to why even if criteria for successful vaccination met, can still prove extremely difficult to eradicate disease? (develop disease)

Answer 45

may develop disease immediately after vaccination but before their immunity levels high enough to prevent it these individuals may harbour pathogen + reinfect others

Question 46

Reasons as to why even if criteria for successful vaccination met, can still prove extremely difficult to eradicate disease? (mutate)

Answer 46

pathogen may mutate frequently, so its antigens change suddenly rather than gradually means that vaccines suddenly become ineffective as new antigens on pathogen no longer recognised by immune system

Question 47

What happens as the immune system can no longer recognise the antigens of the pathogen?

Answer 47

immune system doesn't produce antibodies to destroy pathogen

Question 48

Example of antigenic variability?

Answer 48

happens with influenza virus, which changes its antigens frequently

Question 49

What happens to immunity due to antigenic variability?

Answer 49

immunity short-lived

Question 50

Reasons as to why even if criteria for successful vaccination met, can still prove extremely difficult to eradicate disease? (varities)

Answer 50

may be so many varieties of particular pathogen that it's almost impossible to develop vaccine that's effective against them all

Question 51

Reasons as to why even if criteria for successful vaccination met, can still prove extremely difficult to eradicate disease? (hiding)

Answer 51

certain pathogens 'hide' from body's immune system, either by concealing themselves in cells, or by living in places out of reach i.e. within intestines e.g. cholera pathogen

Question 52

Reasons as to why even if criteria for successful vaccination met, can still prove extremely difficult to eradicate disease? (objections)

Answer 52

individuals may have objections to vaccination for religious, ethical or medical reasons

Question 53

Ethical issues with vaccines (production + development)

Answer 53

production of existing vaccines + development of new ones often involve use of animals

Question 54

Ethical issues with vaccines (side effects)I

Answer 54

side effects may sometimes cause logn-term harm

Question 55

Ethical issues with vaccines (testing)

Answer 55

on whom should vaccines be tested, how should trials be carried out

Question 56

Ethical issues with vaccines (where to trial)

Answer 56

acceptable to trial new vaccine with unknown health risks only in country where targeted disease common?

Question 57

Ethical issues with vaccines (compulsory)

Answer 57

should vaccination be compulsory and can you opt out- on what basis e.g. religion