Vaccines and Antigenic Variability

Question 1

What is a vaccine?

Answer 1

It contains antigens from a dead/weakened pathogen which stimulate the immune response to produce antibodies/plasma cells/memory cells

Question 2

What happens if you are infected post vaccination?

Answer 2

It is a secondary response because you already have memory B-cells for the complimentary antibody therefore you don’t feel symptoms

Question 3

Why are vaccines usually injected?

Answer 3

If taken orally they may be to big to absorb or they can be broken down by the stomach acid

Question 4

What is antigenic variability?

Answer 4

The ability of a pathogen to change the antigens on its surface so the antibodies produced by your memory B-cells are no longer complimentary are upon reinfection you have to go through the primary immune response

Question 5

How can the same pathogen have different antigens?

Answer 5

• Antigenic variability

- Pathogen may have multiple strains