Vaccines Flashcards
What is a vaccine?
A dead or weakened pathogen which stimulates the production of memory cells.
What is herd immunity?
If enough people have a vaccine the disease will not spread through a population.
What is antigenic variablity?
-Some pathogens change their surface antigens due to mutations.
-Memory cells don’t recognise different antigens so need new primary response.
-So new vaccines made.
Why are vaccines not fully effective?
-Fails in certain individuals.
-Pathogens can mutate.
-Can hurt animals when testing.
What are the diffences between passive and active immunity?
Passive:
-Antigen exposure not needed.
-Antibodies not produced.
-Immediate but short-term.
Active:
-Antigen exposure is needed.
-Antibodies are produced.
-Is a slow process but long lasting (forms memory cells).
