vaccines Flashcards
what is a vaccine?
a treatment which builds the bodies immunity to a specific type of infection. derived from a dead pathogen.
what is a vaccination?
the process of administering a vaccine
how does a vaccination work?
viruses are introduced to the body as foreign antigens, weathered down (attenuated), or dead in order to ensure they don’t act up and attack cells. when foreign antigens enter the lymphatic system, certain B-lymphocytes are stimulated to undergo cell division- most of these B-lymphocytes are stimulated to turn into plasma cells, which in turn produce more antibodies. these antibodies combine with the antigen and destroy them.
what do B cells do?
- form memory cells
- produce antibodies
what are the 4 types of vaccines?
- dead organisms
- living attenuated organism
- toxoids (harmless toxin)
- sub-unit (fragment of pathogen)
how are vaccines prepared?
- vaccines are prepared when they are weathered down by taking toxins and inactivating them within a chemical (becomes a toxoid)
- living attenuated vaccines are weathered down
what is a traditional vaccine?
-use a dead pathogen from a virus and are injected via a needle
what are edible vaccines?
-are transgenic/ plant and animal based materials that when ingested trigger an immune response. they are similar to traditional vaccines as they contain fragments of DNA from an original pathogen- these fragments code for a specific protein within the body that will defend if the body ever comes into contact with the virus.
how are edible vaccines made>
when DNA from a plant is extracted and combined with a RNA strand of a particular pathogen to undergo protein synthesis (sub-unit vaccination). RNA cannot reproduce.. after protein synthesis occurs, a specific antigen is derived and placed back into the plant matter for growth or consumption.
pros of traditional vaccines
- tested and proven to be effective
- administered in the correct dosage and it’s a relatively quick process of administering the needle, as well as the time taken for the immunity to work is relatively quick
- designed to last long-term and to protect against deadly diseases- not just the common cold
cons of traditional vaccines
- expensive to be made
- storage and travel is difficult as they need to be kept in certain conditions- making them travelling difficult
- produce poor mucosal response
- don’t work fully if there is not a herd community effect
what is the herd community effect?
-this entails that the majority of society receive the vaccinations in an attempt to not only protect themselves but those that cannot receive the vaccinations as they are either too young, immuno-suppressed, their body cannot respond to the vaccine or for other medical reasons
pros to edible vaccines
- allow for anyone to be able to take the vaccine without the help or administration from a medical professional.
- cheap
- no specific storage needs- easy dispersal across the globe
- Oral administration to Mothers may also be effective for immunising the foetus as these transgenic antibodies are transferred over through the uterine lining and breast feeding.
- promote mucosal immunity
cons to edible vaccines
- The individual may develop immune tolerance towards the particular pathogen
- Dosages are not as clear as they may vary
- Low doses may mean not enough production of antibodies, yet too much dosage could result in immune tolerance.
- The validity of the vaccine may only be effective if the food is prepared at a certain level- for instance potatoes would have to be ingested raw
concerns with ethics surrounding immunisation?
- concern of making immunisation a legal requirement.
- What is the balance between a personal choice and protecting members of the public?
- Should there be exemptions to members of the public who’s medical conditions conflict with receiving a vaccination?
- people should be advised of all the positives and negatives of the immunisation before giving informed consent.