Principles Of Immunisation Flashcards
What are the two types of immunity and what do they involve?
Adaptive immunity is active and involves infection or exposure, or immunisation or vaccines.
Innate immunity is passive and involves placental transfer of IgG or colostral transfer of IgA, or immunoglobulin therapy or immune cells.
They are both is specific but only adaptive has memory.
What are the advantages of passive immunity?
It’s a quick fix and means immediate protection.
What are the disadvantages of passive immunity?
It’s short term so has no memory.
Serum sickness is when the incoming antibody is seen as a foreign antigen by the host so it results in anaphylaxis.
Graft versus host disease (cell grafts) is when incoming immune cells reject the recipient.
What is an example of natural passive immunity?
Maternal immunoglobulins can be transferred to the foetus or neonate using a specialised mechanism involving the neonatal Fc receptor.
Name some examples of artificial passive immunity
Snake/spider bites or stings need a passive infusion of specific antibody for the toxin.
Hypogammaglobulinaemia needs a primary or secondary infusion of gamma globulins to reduce infection.
Rabies immunoglobulin needs a post exposure prophylaxis together with vaccination.
What is a vaccination?
A vaccination is the administration of antigenic material to stimulate an individual’s immune system to develop adaptive immunity to a pathogen.
What is a conventional vaccine that kills the whole organism?
It targets the organism such as polio.
It is effective but booster shots are likely required. Virus must be killed.
What are attenuated whole organism conventional vaccines?
They’re mainly for viruses. An avirulent strain of the target organism is isolated. It simulates natural infection. A problem is it can revert back to virulent form.
What are subunit vaccines?
Recombinant proteins that are safe but not very immunogenic without an effective adjuvant.
Such as Hepatitis B surface antigen.
What is a toxiod vaccine?
The toxin is treated with formalin so it retains its antigenicity but not toxic activity. Only induces immunity against the toxin not the organism that produces it.
Tetanus and diphtheria.
What are two temporary and permanent contraindications of vaccination.
Febrile illness and pregnancy (live attenuated vaccines) are temporary stoppers.
Allergy and immunocompromised people are permanent stoppers.
What is herd immunity and why is it effective?
A certain threshold of vaccination that will protect members that aren’t vaccinated.
Babies who are too young to be vaccinated against whooping cough (under 2 months) are protected if their older siblings are vaccinated.
What makes a good vaccine?
Potent antibody response.
Potent CD8+ cytotoxic T cell response.
CD4+ T helper response.
Memory
What are some challenges that vaccines face?
Protection of vulnerable groups.
Antigenic shift and drift.
Persistence of protection.
What is and what is the purpose of the cold chain network?
It is a process ensured to protect the quality of vaccines from manufacture to point of administration including feedback.
