Flashcards in Immunisation Deck (20):
Vaccination is considered the single most effective medical intervention so far second only to what?
Access to clean water
There are 3 strategies of vaccination what are they?
1) Selective protection of the vulnerable
2) Elimination - herd immunity
What are the 5 possible programmatic aims of vaccination programmes?
1) Prevent deaths
2) Prevent infection
3) Prevent transmission (secondary cases)
4) Prevent clinical cases
5) Prevent cases in certain age groups
What is the single largest aim of vaccination programmes?
To reduce mortality and morbidity from vaccine preventable infections
What is meant by passive immunity?
Either vertical transmission of auto-Ab from mother to foetus & breastfeeding
Or injection of human immunoglobulin
What is meant by active immunity?
Immunity arising from natural infection, or injection of inactivated or attenuated live organisms
What is meant by immunologic memory?
The persistence of protection for many years after natural infection or vaccination
Name the 4 different types of antibody?
IgM, IgG, IgA, IgE
What is the difference between primary immune response and secondary immune response and which Ab are involved?
Primary immune response develops in the weeks following first exposure to an Ag - mainly IgM antibody
Secondary immune response occurs on re-exposure and is faster and more powerful
Mainly IgG Ab
How basically do antibodies produce immunity?
1) Ab produced from B lymphocytes
2) Ag binds non-specifically to variable region of Ab (Ig) molecule, this triggers clonal expansion
3) 1st wave of IgM production, followed by IgG production
4) IgG bonds tightly to Ag and through simultaneous complement binding facilitates the destruction of the Ag bearing micro-organism
5) When infection resolved levels of IgG decline
6) However one set of the IgG producing B lymphocytes persists with the ability to recognise that specific Ag = immunological memory
Give 4 different vaccination programmes which use live organisms?
3) Yellow fever
Give 3 different vaccination programmes which use inactivated organisms?
Give 2 different vaccination programmes which use components of organisms?
Give 2 different vaccination programmes which use inactivated toxins?
In what disease is human immunoglobulin from pooled plasma sometimes injected as prophylaxis?
Measles - HNIG
In what diseases can specific human immunoglobulin be injected as prophylaxis? 5
3) Hep B
What are the 3 advantages of live vaccines?
1) Single dose often sufficient to induce long-lasting immunity
2) Strong immune response evoked
3) Local and systemic immunity produced
What are the 5 disadvantages of live vaccines?
1) Potential to revert to virulence
2) Contraindicated in immune-suppressed patients
3) Interference by viruses or vaccines and passive antibody
4) Poor stability
5) Potential for contamination
What are the 3 advantages of inactivated/killed vaccines?
2) Constituents clearly defined
3) Unable to cause the infection