treatment of disease Flashcards
outline the history of vaccinations
they were first developed by edward jenner in the 1700s when he developed the first small pox vaccine
what are vaccines
they are suspensions of antigens that are intentionally put into the body to induce long term artificial active immunity
they allow B-cells to produce antibodies + memory cells
- this allows for a stronger secondary immune response if infection occurs
what are the 2 types of vaccines
live attenuated and inactivated
live attenuated vaccines
- what are they made of
- how do they work
- limitations
- benefits
- examples
- contain whole pathogens that are weakened
- these multiply slowly and allow the body to recognise the antigens + trigger an immune response + the creation of antibodies
- can be unsuitable for people who are immunocompromised
- produces a stronger + longer lasting immune response
e.g. MMR vaccine
live attenuated vaccines
- what are they made of
- how do they work
- limitations
- benefits
- examples
- contain whole pathogens that are killed / parts of pathogens e.g. antigens, harmless forms of toxins
- they cannot cause disease as pathogens are not living
- can cause mild side effects, do not trigger strong + long lasting immune responses, often require booster doses
- safe for those with weak immune systems
e.g. polio vaccine = a whole pathogen / diphtheria = toxin vaccine
how can vaccines stop disease
they prevent large scale spread of disease, often they are offered by the government as preventative measures against epidemics
e.g. the young are given vaccines for once harmful diseases, like measles
they also give long term / life long immunity
34problems with vaccines
- some people have poor responses and may be unable to produce the antibodies e.g. if malnourished
- antigenic variation means vaccine may not trigger the same immune response / allow for immunity
- diseases caused by eukaryotes may have too many antigens making it too difficult to make effective vaccines that prompt immune system quickly enough e.g. malaria
- viruses can change their antigens by antigenic drift, antigenic shift, antigenic concealment, or crossbreeding between different strains of virus
antigenic drift definition
small changes in antigens over time which can prevent the pathogens from being recognised
antigenic shift definition
large changes in antigens which can prevent the pathogens from being recognised
antigenic concealment definition
pathogens are able to coat their body in host proteins or hide in cells, therefore not able to be recognised
herd immunity definition
when a population has a sufficiently large portion of vaccinated + immune individuals, which provides immunity for the entire population as it prevents the spread of disease
why is herd immunity so beneficial
people who have weak immune systems, are children, or cannot be vaccinated can still be protected against the disease
ring immunity definition
when people living or working near a vulnerable or infected person are vaccinated to prevent them from catching + transmitting disease, protecting others who aren’t immune
what are 2 general challenges of eradicating disease through vaccines
- some pathogens operate in more complicated mechanisms, for which successful vaccines / treatments have not yet been developed
- some diseases that could be eradicated haven’t because vaccine rates are too low, this is most common in areas with unstable political situations or a lack of public health facilities
why is drug discovery important
maintaining drug discovery and research allows scientists to keep up with increasing antibiotic resistant strains
give 4 ways new drugs can be developed
- genome analysis to find candidate genes that could code for potential drugs
- identifying molecules that fit into drug targets
- modifying pre-existing drugs, using computer programming
- identification of useful compounds produced by organisms
what is a limitation of drug discovery
drug development requires a lot of time + money, and drugs must pass several trials before approval
synthetic biology definition
this is an area of research that aims to create new biological parts / systems or to redesign pre-existing ones - this requires the assembly of an entirely new genomes, which will operate in novel ways
give an example of synthetic biology in drug development
artemisinin - a commercially produced anti malarial drug
- E.coli and yeast are completely genetically reprogrammed - through the process of synthetic biology - to produce the drug on a large scale
how is personalised medicine different to most disease treatment methods
it involves the development of more targeted drugs to treat a variety of human diseases + the development of synthetic tissues - unlike the universal approach often applied to drug prescription for treatment
how does personalised medicine work
information gathered from genome projects can be used to develop genomic medicine - this allows drs to prescribe the most effective drugs based on genomes, as between individuals there are differences in DNA base sequences
- this approach is especially useful in cancer medicines
what is genetic screening
a form of personalised medicine, when genomes of individuals are examined and individuals with a high chance of developing specific diseases are identified and offered preventative measures
give an example of a drug initially found in microorganisms
penicillin
- discovered by alexander flemming
- initially from fungi
- this is an antibiotic, so it is effective against bacterial infections
antibiotics definition
chemical substances that inhibit or kill bacterial cells with little to no harm to human tissue / other organisms
- this is possible as they target prokaryotic features
