vaccinations Flashcards
(45 cards)
when is the BCG vaccination given and for what illness?
neonatal
given to children susceptible to TB
when is Hep B given?
first year if born to infected mother
what are the main contra-indications for immunisation?
- Anaphylaxis to a previous dose
- Immunosuppression
- Pregnancy
- Postpone if acutely unwell
Name bogus contra-indications?
Asthma, antibiotics, breast feeding, neonatal jaundice, prematurity, previous history of infection, allergy
what must you do if several live vaccinations are given at the same time?
minimum interval of 3 weeks between them
what diseases dont have a vaccine available to them yet?
malaria, worm infestation, TB, respiratory disease, HIV/AIDS, measles
what is herd immunity?
- The idea that you should vaccinate a certain percentage of a population that will protect the remaining unvaccinated individuals (around 85%).
- Depends on the pathogen, but generally 90% is required for full HI
why may parents not vaccinate their child?
for fear of side effect, judging the risk of vaccine to be higher than the small risk of catching infection
when may herd immunity not work to prevent an infection?
Highly contagious infections like chicken pox, whooping cough and measles
what are features of an effective vaccine?
safety protection longevity neutralising antibodis protective t cells practicality
what considerations should be made when designing a vaccine?
• Whole pathogen or recombinant protein?
o Live attenuated or inactivated vaccine
• Does the vaccine require an adjuvant?
o Injected with vaccine to fool body there is an infection
• Which vaccination route? (Mucosal, injection).
what are you testing when testing a vaccine and what problems may occur?
Reactions to vaccine administration o Anaphylactic reactions o Fever / febrile convulsion o Local reactions o Reversion of live vaccines to ‘wild type’
Problems when pathogen encountered
o Vaccine ineffective
o Heightened immune response to illness
what is a vaccination?
improves quality of immune system to fight against a pathogen in the future
what is an immunisation?
protecting you from a pathogen but only temporarily
what are the types of active immunisation?
- Inactivated – heat-treated
* attenuated – a weaker strain
what are examples of passive immunisation?
receiving antibodies, maternal antibodies from mother to baby
what are modern vaccines?
recombinant peptide vaccines, DNA vaccine, therapeutic vaccines
explain the process of passive immunisation?
- Give injection of killed pathogen
- 10 days later take a blood sample and separate blood cells from serum
- Serum includes neutralizing antibodies
- The serum is then transferred to a different animal
- That animal is then challenged with a live pathogen animal survives
when is passive immunisation given?
given to counteract insect/animal venom
what serum is used usually in passive immunity?
horse serum
what are the problems with passive immunity?
- The immunisation effect lasts for as long as the antibody remains active – a few months at most
- The patient makes an immune response against the serum (can cause “serum sickness”)
what were the 2 types of vaccines or polio?
inactivated vaccine - injected, marinated in formalin, unable to replicate (deactivated)
attenuated vaccine - oral, live weakened polio virus
describe the effects of the inactivated polio vaccine
o Vaccine generates good humoral immunity
o No chance of disease (but often side effects)
describe the effects of the attenuated polio vaccine?
o Virus can replicate but doesn’t usually cause disease
o The vaccine generates humoral and cell-mediated immunity
o However, occasional polio in vaccinated patients.
