Test 2 lecture 7 vaccines

Question 1

What is a good response to:
Vaccines don’t work. My dog still got kennel cough when he was last boarding even though he got the vaccine while he was boarding.

Answer 1

vaccines are not meant to prevent disease, they are meant to decrease the severity of a clinical disease, without the vaccine a pet would have a much more severe reaction

Question 2

Rebuttal to: My horse is all natural. She can’t have any vaccines because they all contain toxic adjuvants.

Answer 2

not all vaccines have toxic adjuvants

Question 3

Rebuttal to: I have a small, young dog and the risk of a vaccine reactions is too high

Answer 3

vaccines are not medications

based on stats- make as many animals as immune as possible (reaction is from number of different antigens, not the amount of an individual antigen)

individuals all respond in different ways

pet reactions are rare and there are ways to decrease reactions, separating vaccines and Benadryl

Question 4

rebuttal to:
I don’t want rabies in my house because of my small children and I heard the vaccines can be shed after they are given

Answer 4

rabies is a dead vaccine therefore it does not shed
whole cell virus incapable of replicating
-this is why you have to booster- not as effective as live vaccine

Question 5

what do vaccines do?

Answer 5

Prevent Clinical Disease

• Reduce Severity of Clinical Disease (may not always protect).
• Prevent spread (less susceptible pop’n)
• Assure routine veterinary care

Question 6

4 types of immunity

Answer 6

Question 7

vaccination is a type of ___ immunity

Answer 7

active artificial

Question 8

live vaccines

Answer 8

Question 9

dead vaccines

Answer 9

Question 10

rabies is a ___ vaccine

Answer 10

killed

unable to replicate → no shedding

no memory response → usually boosted (but we do not boost rabies because incubation time is so long)

Question 11

lepto is a type of

Answer 11

inactive (killed) vaccine

bacterin (dirtier)

Question 12

bacterin

Answer 12

culture of bacteria that is killed by boiling and spun down and left over is used for vaccines

(lepto is a type of killed vaccine)

Question 13

killed vaccines usually need ___

Answer 13

adjuvants

leads to fewer doses and better response

makes more safe

Question 14

examples of adjuvants

Answer 14

Alum

• Unphosphorylated CpG motif
• Freund’s adjuvant (mycobacterium in mineral oil)
• Monophosphoryl lipid A

Question 15

live vaccines

Answer 15

induce humoral (antibody mediated) and cell mediated (T cell)

mimic natural infection

all oral/nasal vaccines are live vaccines

Question 16

why are oral and nasal vaccines attenuated

Answer 16

to produce IgA at mucosal surfaces

Question 17

how to attenuate a vaccine?

Answer 17

live organism is passed through an off target host → every time it goes through a host it changes slightly until you get to a version of the virus that is less effective

safer virus/ weaker virus

Question 18

recombinant vaccine

Answer 18

virus vectored→ non pathogen virus carries target antigen

DNA vaccine→ DNA of the antigen is injected into the host cell

subunit → purified protein antigen from engineered bacteria

chimeric (polyvalent) → engineered protein to express multiple antigens

Question 19

Toxoid

Answer 19

killed vaccine → anti toxin

Denatured toxin that induces humoral immunity to prevent effects of toxin (i.e. botulinum, tetanus, rattlesnake venom).

• No longer active but can produce humoral immunity.

Question 20

DIVA

Answer 20

Some vaccines you NEED to be able to differentiate between vaccinated and infected animals.

• Killed Foot-and-Mouth Disease Vaccines can NOT be used in FMD free countries (cross-reacts with regulatory testing).
• Differentiation of Infected from Vaccinated Animals (DIVA).

Question 21

Please look-up a DIVA vaccine and in <20 words be able to describe the principle of differentiation (how you can differentiate between diseased vs.
vaccinated animals).

Answer 21

DIVA stands for Differentiating Infected from Vaccinated Animals and may utilise a vaccine (sometimes referred to as a marker vaccine) which is based on a different strain than the infective strain, enabling a diagnostic test to differentiate between vaccine-induced antibodies and antibodies against the infective strain.

TB test for cows→ infected are +, vaccination are 0