Vaccines

Question 1

What is passive immunity?

Answer 1

Immunity achieved by preformed immunoglobulins from previously infected or immunized individuals. These antibodies provide immediate protection, but dissipate within a few weeks to months and do not generate memory.

Question 2

What is one example of natural passive immunity?

Answer 2

Passive immunity generated through the natural transfer of maternal antibodies to the fetus through placental circulation and breast milk.

Question 3

What is one example of induced passive immunity?

Answer 3

When a mixture of nonspecific antibodies reflecting previous exposures of plasma donors to various antigens are injected into patients to confer passive immunity.

Question 4

What is IVIg?

Answer 4

Intravenous immunoglobulin is a last resort method of induced passive immunity where individuals are given a mixture of antibodies from multiple blood donors.

Question 5

What is immunization?

Answer 5

The gaining of protective immunity through exposure to a pathogen (infection, vaccination).

Question 6

What is vaccination

Answer 6

Intentionally exposing an individual to a pathogen with the intention of generating protective immunity.

Question 7

What is natural active immunity?

Answer 7

Pathogen-specific immunity conferred through infection.

Question 8

What is induced active immunity?

Answer 8

Pathogen-specific immunity conferred through vaccination.

Question 9

What are four common ways that result in vaccination failing to immunize.

Answer 9

Administration, patient genetics, batch quality, and pathogen changes.

Question 10

What are the three components of a vaccine?

Answer 10

The antigen (the target seen b the adaptive immune system), the adjuvant, and the route/dose.

Question 11

What are live attenuated vaccines?

Answer 11

Vaccines containing a weakened form of the pathogen.

Question 12

What are the strengths of live attenuated vaccines?

Answer 12

Attenuated microbes will multiply in the recipient, leading to a more robust immune response, both cellular and humoral. Usually lifelong immunity can be conferred with only 1 or 2 doses.

Question 13

What are the weaknesses of live attenuated vaccines?

Answer 13

Attenuated vaccine strain could possibly revert back to an active form, so health professionals and immunocompromised individuals cannot be given this vaccine. These vaccines must also be refrigerated to stay potent.

Question 14

What are killed virus vaccines?

Answer 14

Vaccines containing inactivated organisms or parts of them.

Question 15

What are the strengths of killed vaccines?

Answer 15

They pose no risk of vaccine associated infection, and do not require refrigeration.

Question 16

What are the weaknesses of killed vaccines?

Answer 16

They provide weaker and short-lived immune responses as the pathogen cannot replicate, and they are unable to actually infect the host. This necessitates several doses/ booster shots.

Question 17

What are subunit vaccines?

Answer 17

Vaccines containing antigens from pathogen that best stimulate the immune system.

Question 18

Do subunit vaccines elicit both cellular and humoral immunity?

Answer 18

No, they stimulate antibodies but no T cell responses.

Question 19

What is one weakness of subunit vaccines?

Answer 19

They are not useful to confer immunity against pathogens that are antigenically diverse and variable.

Question 20

What are toxoid vaccines?

Answer 20

A type of subunit vaccine used when a bacterial toxin is the man cause of illness. These vaccines contain chemically altered toxin or synthetically engineered harmless toxin.

Question 21

What are engineered vaccines (recombinant vector vaccines)?

Answer 21

Vaccines that contain non-cytopathic or attenuated virus/bacteria with genes encoding microbial antigens.

Question 22

What are the strengths of engineered vaccines?

Answer 22

They generate a true infection that induces both humoral and cellular immunity.

Question 23

What are DNA and RNA vaccines?

Answer 23

Vaccines where a gene for an antigen of interest is clones into a bacterial plasmid that, upon injection into a host cell, uses host cell machinery to direct protein synthesis of the antigen.

Question 24

What are the strengths of DNA and RNA vaccines?

Answer 24

They elicit “designer” immune responses, are low costing, and can induce both humoral and cellular immunity.

Question 25

What are the three ways that adjuvants help in stimulating an immune response?

Answer 25

They prolong exposure of the antigen to the immune system, they promote uptake of the antigen (phagocytosis), and they activate the innate immune system by exhibiting co-stimulatory signals.

Question 26

What are adjuvants usually made up of?

Answer 26

Usually made up of a mixture of oils, metal salts (alum), microbial cell wall components (mycobacteria), nucleic acids, and preservative (mercury).

Question 27

How does alum stimulate the immune system?

Answer 27

It creates a depot effect, meaning the slow release of antigen to the immune system. Crystals from the depot are too large to phagocytose, irritating and increasing innate immunity.

Question 28

What are two common routes of vaccine administration?

Answer 28

Subcutaneous or intramuscular, and intranasal or oral.

Question 29

What are the benefits of innoculating individuals subcutaneously or intramuscularly?

Answer 29

Slow absorption of antigens, which will eventually be transported to local lymph nodes, resulting in the formation of memory cells that migrate throughout the entire body.

Question 30

What are the benefits of innoculating individuals intranasally or orally?

Answer 30

Rapid absorption and involvement of mucosal lymphoid tissues, which does not generate a body wide immune response.

Question 31

What is the name for immunity generated by innoculation subcutaneously or intramuscularly?

Answer 31

Systemic immunity.

Question 32

What is the name for immunity generated by innoculation intranasally or orally?

Answer 32

Mucosal immunity.