Test 2 lecture 7 vaccines Flashcards
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.
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
Rebuttal to: My horse is all natural. She can’t have any vaccines because they all contain toxic adjuvants.
not all vaccines have toxic adjuvants
Rebuttal to: I have a small, young dog and the risk of a vaccine reactions is too high
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
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
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
what do vaccines do?
Prevent Clinical Disease
- Reduce Severity of Clinical Disease (may not always protect).
- Prevent spread (less susceptible pop’n)
- Assure routine veterinary care
4 types of immunity
vaccination is a type of ___ immunity
active artificial
live vaccines
dead vaccines
rabies is a ___ vaccine
killed
unable to replicate → no shedding
no memory response → usually boosted (but we do not boost rabies because incubation time is so long)
lepto is a type of
inactive (killed) vaccine
bacterin (dirtier)
bacterin
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)
killed vaccines usually need ___
adjuvants
leads to fewer doses and better response
makes more safe
examples of adjuvants
Alum
- Unphosphorylated CpG motif
- Freund’s adjuvant (mycobacterium in mineral oil)
- Monophosphoryl lipid A
live vaccines
induce humoral (antibody mediated) and cell mediated (T cell)
mimic natural infection
all oral/nasal vaccines are live vaccines
why are oral and nasal vaccines attenuated
to produce IgA at mucosal surfaces
how to attenuate a vaccine?
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
recombinant vaccine
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
Toxoid
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.
DIVA
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).
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).
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