Vaccines (Princ. immunisation) Flashcards
How is active immunity produced?
A foreign antigen triggers an adaptive immune response int he body.
This creates immunological memory (memory cells).
Whats the difference between the initial response & response with active immunirt?
The intitial response is slow & uses not great IgM antibodies.
The future response is much faster, larger & uses more effective IgG antibodies.
Name the 5 types of vaccine that cause active immunity:
Toxoids Conjugate vaccines Attenuated vaccines Killed vaccines Recombinant vaccines
What is an attenuated vaccine?
Organisms that are live but no longer pathogenic.
Produce full immune response but no disease.
How are pathogens attenuated?
Passes through non-human cell cultures repeatedly till they become non-pathogenic.
Why arnt attenuated vaccines given to the immunocompromised or pregnant?
Chance they could still revert to their pathogenic state.
What are the limitations of Attentuated vaccines?
- Needs refrigeration so hard in developing countries.
- Easier for viruses than bacteria
Give an example of an attenuated vaccine?
MMR
BCG (TB) (Bacillus Calmete-Guerin)
How is a pathogen deactivated for a dead vaccine?
Formaldehyde causes chemical deactivation
In what way is a dead vaccine better than live?
Can’t revert to wild-type so not a danger to the immuno-compromised or pregnent.
Why use adjuvants in dead vaccines?
They produce a wekaer immune rseponse so adjuvants reduce the doses needed.
Define Adjuvant
A substance that enhances antibody response
Why wouldnt you always use adjuvants?
They can have inflammatory responses against other proteins/antigens int he vaccine
Give an example of a dead vaccine:
Polio
HEP A
Rabies
What is a toxoid?
A pathogen’s toxin thats been treated with formalin.
