Principles of Immunisation Flashcards
What can adaptive immunity be referred to as
Acquired immunity
What are the advantages of passive immunity
Provides immediate protection
Acts as a quick fix
What are the disadvantages of passive immunity
No immunological memory
May cause serum sickness
Graft (cell graft) vs host disease
What is serum sickness
The incoming antibody is recognised as a foreign antigen by the recipient and results in anaphylaxis
What is graft vs host disease
The incoming immune cells reject the recipient
Describe the process of passive immunity
Serum (antbodies) from immune individual administered to uninfected individual
infection challenged by serum admiistered
Does passive immunity provide specificity
Yes
Describe the process of active immunity
Exposure to microbial antigen through a vaccine or infection
Infection challenged over days or weeks
What does active immunity provide
Specificity
Immunological memory
What is an example of natural passive immunity
Maternal immunoglobulins transferred to the foetus or neonate naturally using a specialised mechanism involving neonatal Fc receptors
What is an example of artificial passive immunity
The passive infusion of antibodies specific for the toxin (e.g. snake/spider bites or scorpion/fish stings)
Post-exposure prophylaxis
How does natural active immunity occur
Through exposure or infection
How does artificial active immunity occur
Through vaccination
Define vaccination
Administration of antigenic material (vaccine) to stimulate an individual’s immune system to develop adaptive immunity to a pathogen
What are common diseases vaccinated against
Measles
Mumps
Rubella
What can measles result in
Rash
What can mumps lead to
Meningitis
Name the types of active immunisation vaccines available
Killed (inactivated) whole organism
Live attenuated whole organism
Subunit (purified antigen) vaccine
Toxoid (modified inactivated toxin)
Describe the killed (inactivated) whole organism vaccine
The target organism (e.g. polio) is killed
Viruses must be effectively heat killed as any live virus can result in vaccine-related disease
What are the advantages and disadvantages of killed (inactivated) whole organism vaccines
Effective and relatively easy to manufacture
Booster shots likely to be required
Give examples of killed (inactivated) whole organism vaccines
Whole-cell pertussis (wP)
Inactivated polio virus (IPV)
Describe live attenuated whole organism vaccines
An avirulent strain of the target organism is isolated to stimulate the natural infection causing it to revert back to the virulent form
What are the advantages and disadvantages of live attenuated whole organism
Very powerful method
Better than killed whole organism vaccine
Requires vaccination
Give examples of live attenuated whole organism
TB (BCG) Measles Rotavirus Yellow fever Oral polio vaccine (OPV)
Describe subunit (purified antigen) vaccines
Uses recombinant proteins
Therefore it introduces the antigen to the immune system but not the viral particles
What are the advantages and disadvantages of subunit (purified antigen) vaccines
Very safe
Easy to standardise
Not very immunogenic without an effective adjuvant
Give examples of subunit (purified antigen) vaccines
Hepatitis B surface antigen (HBsAg)
Human papilloma virus (HPV) proteins
Haemophilus influenzae type B (Hib)
Describe toxoid (modified inactivated toxin) vaccines
The toxin is treated with formalin so the toxoid can retain antigenicity with no toxin activity
What are the disadvantages of toxoid (modified inactivated toxin) vaccines
It only provides immunity against the toxin and not the organism that produces it
Give examples of toxoid (modified inactivated toxin) vaccines
Tetanus toxoid (TT) Diphtheria toxoid
At the age of 2 months (in babies) what vaccinations are required
Diphtheria Tetanus Pertussis Polio Haemophilis influenzae type b Streptococcus pneumoniae Rotavirus
At the age of 12-13 months what vaccinations are required
Haemophilis influenzae type b
Neisseria meningitidis C
MMR
Streptococcus pneumoniae
At the age of 3 months (in babies) what vaccinations are required
Diphtheria Tetanus Pertussis Polio Haemophilis influenzae type b Rotavirus Neisseria meningitidis C
At the age of 4 months (in babies) what vaccinations are required
Diphtheria Tetanus Pertussis Polio Haemophilis influenzae type b Streptococcus pneumoniae
What vaccination is required at the age to 2/3/4 years
Influenza
What vaccinations are required >3 years 4 months
Diphtheria Tetanus Pertussis Polio MMR
What vaccine do females only get between the age of 12-13
HPV
What vaccinations are given between the ages of 13-18
Diphtheria
Tetanus
Polio
Neisseria meningitidis C
Who is given the BCG vaccination
Children who are more likely to come into contact with TB
Who is given the hepatitis B vaccination
Children with a Hep B positive mother
What vaccinations may travellers need to be given
Hepititis A Typhoid Cholera Yellow fever Japanese encephalitis Tick-borne encephalitis Rabies Neisseria meningitidis serogroups A, C, W135, Y
What types of contraindications to vaccinations are there
Temporary
Permanent
Name 2 temporary contraindications to vaccinations
Febrile illness
Pregnancy (cannot be given live attenuated vaccines)
Name 2 permanent contraindications to vaccinations
Allergy
Immunocompromised (cannot be given live attenuated vaccines as they may develop disease from the vaccine strain)
What is herd immunity
The individual who receives the vaccine is protected and less likely to be a source of infection to others
This reduces the risk of unvaccinated individuals being exposed to infection
Individuals who cannot be vaccinated are still able to benefit from the routine vaccination programme
Give an example of herd immunity
Babies under 2 months are too young to be immunised and are at the greatest risk of dying from whooping cough
They are believed to be protected as their older sibling and other children have been immunised and will not be able to pass on the infection
