Immunisation Flashcards
(21 cards)
what is the point of immunisation?
control communicable disease
1) prevent onset of disease
2) interrupt transmission
3) Alter course to limit consequences
how do vaccines work?
teach the immune system to recognise bacteria and viruses. primed and ready.
what are antigens?
parts of bacteria that are recognisable by immune system
proteins or polysaccharides
what are antibodies?
proteins that bind to antigens
very specific to antigens
when the complex is formed, it alerts other immune cells.
how and where are antibodies produced?
b cells - humoral immune system (mature in the bone marrow, triggered to produce antibody when encounter foreign antigen)
t cells - cell-mediated immune system (mature in thymus, CD4+, CD8+, orchestrate response of immune system by binding to other cells and sending out signals)
what is passive immunity?
transfer of pre-formed antibodies
how does passive immunity occur?
mother to baby (placenta for up to 1 year)
person to person/animal (blood donors)
name two examples of antibodies that pass by passive immunity?
human immunoglobulin (HepB, rabies, varicella zoster) anti-toxin (diphtheria, botulinum)
what are some advantages or disadvantages of passive immunity?
advantages
- rapid, post-exposure, outbreak control, used if contra-indication to active vaccination
disadvantages
- short-term protection and window, blood derived, hypersensitivity reaction, expensive
chart the immunity mechanisms
immunity - passive – artificial human IgG
I I
I natural transplacental transfer
I
active – artificial immunisation
I
natural infection
what are the mechanism of vaccine
induce cell-mediated immunity responses and serum antibodies
different vaccines induce different speed and sustainability of response
what types of vaccines are there?
live and inactivated
how does a live vaccine work
an attenuated organism, replicates in the host
how does an inactivated vaccine work
suspension of killed organisms
subunit vaccines
conjugate vaccines
what type of contraindications are there to vaccines
Confirmed anaphylaxis reaction to vaccine component.
Live vaccines: immunosuppression or pregnancy
Egg allergy
Severe latex allergy
Acute or evolving illness.
what term implies population protection
herd immunity
what is the single largest co-ordinated public health programme?
Scottish immunisation programme
protects against 15 different diseases. expanding~1million doses annually.
how are children protected?
routine vaccination schedule that should be followed closely as the science is age-related on risk of disease and level of protection.
what is diphtheria and what organism is responsible?
URTI characterised by sore throat, low grade fever. white adherent membrane on the tonsils, pharynx and/or nasal cavity Corynebacterium diphtheriae (aerobic gram-positive bacterium.
(white throat)
what is meningococcal disease?
invasive infection caused by Neisseria meningitidis. (meningitis, septicaemia or both). can cause lasting neuro damage to 10-15%
spread person to person droplets. incubation 3-5 days (<5yrs & 15-24yrs)
when was the men c conjugate vaccine introduced and why?
1999
throughout the 1990’s the age range of those affected was getting older and there was evidence of clustering
