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Medical Microbiology > Vaccines > Flashcards

Flashcards in Vaccines Deck (14):
1

Vaccine Efficacy

VE (%) = (ARU-ARI)/ARU

2

How do vaccines work?

Ag encounter in tissues. DC migrates into lymphoid tissue, activates T cells (both CD4 and CD8). T cells activate B cells, some of which turn into plasma cells to produce Igs.

3

Class 1 MHC recognized by?

CD8 killer T cell

4

Class 2 MHC recognized by

CD4 helper T cell

5

Why are multiple doses of a vaccine given?

To dramatically increase antibody levels. After a booster, there are shorter lag phases, higher Ab levels, and longer persistence.

6

What do bacterial vaccines promote?

Antibodies to neutralize toxins, promote opsonization/phagocytosis/complement-mediated lysis.

7

What is the peak incidence of H. influenzae, s. pneumo, n.meningitidis? Why?

6-18 mo. Before 6mo, there are still maternal IgGs.

8

Is it possible to develop a vaccine to an encapsulated organism?

Yes of course! Just vaccinate against capsular antigens.

9

Are pure polysaccharide vaccines effective?

Yes, but not in children under 2 years old.

10

How to induce immune response to polysaccharide ag in children?

Conjugate to a protein like tetanus toxoid.

11

How does a Pr-Ps vaccine induce better immunity?

Pr-ps is internalized, protein is degraded and presented to T cells, which will produce cytokines to have B cells make antibodies to PS component.

12

Adjuvant?

Added substance that enhances immune response to a target antigen by inducing concurrent inflammatory response/slowing release of antigen. Mineral oil/alum.

13

Vaccines that contain adjuvants are generally administered which way?

IM

14

What vaccine is least effective?

Pertussis, immunity is short lasting.