Flashcards in 8 - Defence and Vaccination against Bacteria Deck (10):
What are the 2 divisions of acquired immunity?
- directly mediated by antibodies
- mediated by T lymphocytes and NK cells
What are the roles of humoral and cellular immunity?
- toxin neutralisation
- complement binding
promoting phagocytosis through opsonisation
- important in eliminating intracellular bacteria
- interaction of the reactive T lymphocytes and the macrophage is key to clearance of infection
What are the properties of a good vaccine?
A GOOD VACCINE PROVIDES SUBSTANTIAL BENEFIT TO HEALTH AT LOW COST AND LOW RISK
Ideally a vaccine:
Stimulates an effective immune response
Is safe and does not cause adverse reactions
Is inexpensive to manufacture and distribute
Is easy to administer
Should be simple for both manufacturer and regulatory authorities to control
What is herd immunity?
a form of immunity that occurs the the vaccination of a significant portion of the population provides a measure of protection for individuals who have not yet developed immunity
refers to the effect of immunity within a population to reduce transmission of the infectious agent, thereby protecting those who are susceptible (i.e. not immune) to the disease.
The endemic state reflects a balance between the transmissibility of the infectious agent and the level of immunity in the population.
During which stage of a clinical trial is vaccine efficacy determined?
How is vaccine efficacy calculated?
1 - ( attack rate in vaccinated group/ attack rate in unvaccinated group)
What are the 3 main elements of vaccines?
ADJUVANT - to enhance and modulate the immune response
buffers, salts, saccharides and proteins maintain the pH, osmolality and stability of the vaccine
What are conjugate vaccines?
carbohydrate chemically linked to immunogenic protein
- T cell recognition of protein carriers enhances B-cell activation
- promotes efficient antibody response to polysaccharide capsule
What are live attenuated vaccines?
a vaccine prepared from live microorganisms or functional viruses whose disease-prodding ability has been weakened, but whose immunogenic properties have not