Vaccines

Question 1

What are the differences between passive and active immunization?

Answer 1

Passive- provides rapid but temporary protection

Active- vaccines. Take longer to induce but provides longer lasting immunity.

Question 2

Why would you ever use passive immunity?

Answer 2

Artificial transfer of immunoglobulins against toxins or venoms such as for the treatment of tetanus or snake bites

Question 3

What are five different categories of vaccines that can be produced against an infectious agent?

Answer 3

1. modified live vaccines
2. heterologous
3. inactivated
4. recombinant
5. DNA

Question 4

What are some of the benefits of vaccines that contain living organisms?

Answer 4

Require fewer and smaller doese
Induce IFN and stimulate both humeral and CMI
Induce longer lasting immunity
Are relatively cheap

Question 5

What are some of the benefits of vaccines that do not contain living organisms?

Answer 5

They are more stable and storable

They do not replicate; unlikely to cause disease and will not spread

Question 6

What are modified live vaccines?

Answer 6

weakened/altered to be less pathogenic

genetically attenuated or culture attenuated

Question 7

What are heterologous vaccines?

Answer 7

vaccines that use a different, less virulent strain. ex- adeno II

Question 8

What are recombinant vaccines?

Answer 8

Purified subunit- purify out a component of the organisms

Recombinant- utilize a vector to produce a sub-unit

Question 9

What are the three primary functions of adjuvants?

Answer 9

1. slow the removal of Ag resulting in a longer response
2. Enhance Ag presentation
3. Stimulate TLR response

Question 10

What is the difference between a toxoid and a bacterin?

Answer 10

toxoid- denatured bacterial exotoxins (Tetanus)

Bacterin- vaccine containing killed bacteria

Question 11

What is the difference between and exotoxin and an endotoxin?

Answer 11

exo- Gram negative bacteria, outer wall LPS, bind TLRs, induce cytokines

endo- toxic proteins secreted by dying bacteria.

Question 12

Why do young animals receive a series of vaccines?

Answer 12

Maternal antibody interferes with the vaccine, so it is important to vaccinate multiple to make sure animal is properly innoculate

Question 13

At what point should you revaccinate an adult animal?

Answer 13

Depends on the animal- consider disease state, age of animal, and duration of immunity of the vaccine

Question 14

Why don’t vaccines always work (3)?

Answer 14

1. Incorrect administration- inappropriate route, vaccine degradation
2. Animal fails to respond- maternal Ab, Immunocompromised, Biologic variation
3. Animal responds- already infected, wrong strain/organism, non-protective antigens

Question 15

What is the goal in a population strategy for vaccination?

Answer 15

The goal in a population is to get adequate responses in the majority of animals

Question 16

Describe the 3 main reasons for adverse vaccine reactions

Answer 16

1. Normal toxicity- induction of an immune response. seen more often in small animals
2. Significant vaccine error- manufacture/administration, contamination, abnormal toxicity, residual virulence
3. Inappropriate immune response- majority of these are hypersensitivity responses (I, III, IV)