Vaccination Flashcards
Passive Immunity
Administration of preformed antibody from an immunised animal
Provides immediate but temporary resistance
E.g. colostrum, yolk sac
Active Immunity
Protection due to development of an immune response in an individual following stimulation with antigen in either a vaccine or during infection
Ideal Vaccine
High antigenicity No side effects Cross protection Easy administration Long lasting Storage Stimulate T & B cells, plus their memory cells Stimulate antigen presenting cells i.e. macrophages
Attentuation
Reduces the virulence of the living pathogen (so they cant cause disease)
Often involves adaption of organism to new environment
Repeated culture in foreign host - e.g. canine distemper virus
Growth in different host e.g. eggs
Attentuation
Reduces the virulence of the living pathogen (so they cant cause disease)
Often involves adaption of organism to new environment
Repeated culture in foreign host - e.g. canine distemper virus
Growth in different host e.g. eggs
Antigen inactivation (vaccine)
Antigen must remain antigenically similar to the living organism - avoid protein denaturation or lipid oxidation
Use chemicals such as formaldehyde which form cross links between proteins and nucleic acids - provides structural integrity
Bacterins
Vaccines that contain killed bacteria
Adjuvant
A substance that accelerates, prolongs or enhances antigen specific immune responses when used concurrently with a vaccine antigen.
Form a depot (small granuloma) on injection which slows release of antigen and provides continual exposure
Ongoing presence of antigen helps to sustain response
Adjuvant
A substance that accelerates, prolongs or enhances antigen specific immune responses when used concurrently with a vaccine antigen.
Form a depot (small granuloma) on injection which slows release of antigen and provides continual exposure
Aluminium salt adjuvants
on injection form a depot (small granuloma) so slows rate of antigen elimination
Water-in-oil adjuvant
Depot forming adjuvant
Stimulates chronic immune response to form depot
Surface active agent adjuvants
Stimulate antigen processing and presentation
Irritant and proinflammatory
Six rules of thumb for active vaccination
- Newborns are passively protected by maternal antibodies
- Once born, active immunisation is only successful after passive immunity has waned
- Prevalence of the disease
- Age and class of stock
- Need for booster
- Seasonal occurrence