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Flashcards in VACCINATION Deck (47)
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What is immunity

the ability of an organism to resist infection


What 2 forms can immunity take

passive or active


What is passive immunity

immunity that doesn't require direct contact with the pathogen or its antigen


How is passive immunity produced

introduction of antibodies into individuals from an outside source


Is the lasting immunity with passive immunity and why

no, because the antibodies are not produced by the individual so the antibodies are not replaced when broken down & no memory cells are formed


What are 2 examples of passive immunity

anti-venom, immunity acquireed by the fetus when antibodies pass across placenta


What are the 2 forms of passive immunity

natural, artificial


What is natural passive immunity

when a baby becomes immune through antibodies recieved from mother via placenta and breast milk


What is artificial passive immunity

when you become immune after being injected with antibodies from someone else


What is active immunity

immunity you get when your immune system makes its own antibodies after being stimulated by an antigen


How is active immunity produced

stimulating the production of antibodies by the individuals own immune system


What is necessary for active immunity

direct contact with the pathogen or its antigen


Is active immunity long lasting

yes generally


What are the 2 types of active immunity

artificial and natural


What is natural active immunity

when an individual becomes infected with a disease under normal circumsances and the body produces its own antibodies


What is artificial active immunity

when an individual becomes immune to a disease through being given a vaccination to trigger a response by the immune system but the individual does not suffer symptoms


What is vaccination

the introduction of the appropriate disease antigens into the body via either injection or mouth


What do vaccinations contain

antigens that are either free or attached to a dead/attenuated pathogen


What does a vaccination lead to the production of

memory cells


How much antigen is there in each vaccination and why

small amount, only small amount needed to trigger immune response & create memory cells, so saves money


What is the material introduced within a vaccination called



What is herd immunity

when a sufficiently large proportion of the population has been vaccinated in order to make it difficult for the pathogen to spread


What does attenuated mean



What are the 2 methods of taking vaccinations

1) orally
2) injected


What is a disadvantage of taking a vaccination orally

could be broken down by enzymes in the gut, ot the molecules of th evaccine could be too large to be absorbed into the blood


Why are booster vaccines sometimes given

to ensure that memory cells are produced


What is a vaccination used as

precautionary measure to prevent individuals contracting a disease


What is a vaccination not used as

a cure for someone that already has the disease


What does the success of a vaccination programme depend on (5 points)

1) suitable vaccine must be economically available in sufficient quantities
2) must be few side-effects, if any
3) means of producing, storing and transporting the vaccine must be available (hygenic conditions & refrigerated transport)
4) must be means of administering the vaccine properly at the appropriate time (staff must be trained with appropriate skills)
5) must be possible to vaccinate the vast majority of the vulnerable population to produce herd immunity


Why must the vaccine be economically available in sufficient quantities to ensure the success of a vaccination

to immunise most of the vulnerable population


Why must there be few side-effects, if any, to ensure the success of a vaccination

so that the population is not discouraged about getting vaccinated


How does herd immunity work

pathogens pass between individuals when they come close together, so when lots of people are immune it is unlikely that an un-immune person will come in contact with the pathogen so are protected


Why is herd immunity important

not all the population can be vaccinated (very young - immune systems are not fully functional, ill - could be dangerous to vaccinate)


When is the best time to vaccinate to create herd immunity and why

at one time, so for a certain period there are very few people with disease so passing is interrupted


What are the reasons for why vaccination may not eliminate a disease (6 points)

1) vaccination fails to create immunity in some people, e.g. those with defective immune systems
2) individuals may develop diseases immediately after vaccination but before immunity levels are high enough to prevent it, so may habour( keep) pathogen and pass to others
3) pathogen may mutate so its antigens change and are no longer recognised by the immune system (antigenic variability)
4) may be many varieties of a particular pathogen meaning it is impossible to develop a vaccine for them all
5) certain pathogens can 'hide' from the bodys immune system
6) individuals may have objections to vaccinations due to religious, ethical or medical reasons


What is antigenic variability

the mutation of antigens on pathogens


What does antigenic variability lead mean for vaccination

they do not work as the bodys immune system does not recognise the antigen so doesn't produce antibodies


What is an example of a virus that has lots of antigenic variability

influenza virus


What is the immunity to influenze due to its antigenic variability

short-lived and individuals may develop repeated influenze during their lifetime


What is an example of a pathogen that there are many varieties of and how many varieties are there

common cold virus, over 100 varieties


How do certain pathogens 'hide' themselves

concealing themselves inside cells or living in places out of reach


What is an example of a pathogen that 'hides' itself and where does it 'hide'

cholera pathogen, hides in the intestines


What is an example of a disease that people were against

MMR as concerns rose about the cause of autism by the vaccine


What are ethical issues for vaccinations (7 points)

1) production of new vaccines often involves use of animals
2) vaccines have side effects that may cause long-term harm
3) trails with unknown health risks are done
4) should expensive vaccination programmes continue when a disease is almost eradicated even if it stops means less money for other diseases


Compare active and passive immunity (4 points)

1) a=requires exposure to antigen, p=doesn't
2) a=takes a while for protection to develop, p=protection is immediate
3) a=memory cells produced, p=no memory cells produced
4) a=protection is long term, p=protection is short term (antibodies broken down)


What were the issues with the article published about MMR being linked to autism (4 points)

1) author of research had conflict of interests
2) further studies found no link
3) sample size was very small
4) journal declared that if it had known all the facts it would not have published it


Why should all scientific evidence be treated with caution initially (5 points)

1) confirmation of a theory takes time
2) scientists may not be acting independantly so may be biased
3) scientists personal views may influence
4) headlines may be distorted for bias views
5) theories are being modified all the time