principles of immunisation week 5 Flashcards
what is something that the measles virus can do
can wipe out the memory response associated with the adaptive immune system
what are the two types of immunity
adaptive (active/passive)
innate
what are the advantages of passive immunity
- gives immediate protection
what are the disadvantages of passive immunity
- short term effect (no immunological memory)
- serum sickness (incoming antibody seen as foreign and results in anaphylaxis)
- graft vs. host disease (cell grafts only, incoming immune cells reject the recipient)
what are some examples of passive immunity
- placental transfer of IgG
- colostral transfer of IgA
- immunoglobulin therapy or immune cells
what is active immunity
- part of adaptive immunity
- antigen stimulates immune response
- long term immunity (may be life long )
- immunological memory
- no immediate effect but faster and better response to next antigenic encounter
what is vaccination
the administration of antigenic material (a vaccine) to stimulate an individual’s immune system to develop adaptive immunity to a pathogen
what are the different types of vaccines
- live attenuated (LAV)
- inactivated (killed antigen)
- toxoid (inactivated toxins)
- subunit (purified antigen)
what is inactivated (killed whole organism) vaccine
- grow up the virus, treat it, then it’s dead but still immunogenic
- effective and relatively easy to manufacture
- booster shots likely required
- virus must be heat killed effectively because any live virus can result in vaccine related disease
what is live attenuated vaccine
- avirulent strain of target organism is isolated
- can be powerful and better than killed
- stimulate natural infection
- in some circumstances it can revert back to more virulent form of disease
- requires refrigeration
what are subunit vaccines
- recombinant proteins
- generally very safe
- easy to standardise
- not very immunogenic without an effective adjuvant
what is a toxoid vaccine
- modified toxin
- toxin is treated with formalin
- toxoid retains antigenicity but has no toxic activity
- only induces immunity against the toxin, not the organism that produces it
what are some examples of live attenuated vaccines
- tuberculosis
- oral polio vaccine
- measles
- rotavirus
- yellow fever
what are some examples of inactivated (killed antigen) vaccines
- whole cell pertussis (wP)(whooping cough)
- inactivated polio virus (IPV)
what are some examples of subunit vaccines
- Hep B
- acellular pertussis
- haemophilus influenzae type B
- pneumococcal
what are some examples of toxoid vaccine
- tetanus toxoid
- diphtheria toxoid
what vaccines do you get at 2 months old
diphtheria, tetanus, pertussis, polio, haemophilia influenzae type b, streptococcus pneumoniae, rotavirus
what vaccines do you get at 3 months old
diphtheria, tetanus, pertussis, polio, haemophilis influenzae type b, neisseria meningitidis C, rotavirus
what vaccines do you get at 4 months old
diphtheria, tetanus, pertussis, polio, haemophilis influenza type b, streptococcus pneumoniae
what vaccines do you get at 12-13 months old
haemophilis influenzae type b, neisseria meningitidis C, measles, mumps, rubella, streptococcus pneumoniae
what vaccine do you get at 2, 3 or 4 years old
influenza
what vaccines do you get over the age 3 years 4 months
diphtheria, tetanus, pertussis, polio, measles, mumps, rubella
what vaccines do you get aged 12-13 years old
HPV (females only)
what vaccines do you get aged 13-18 years old
diphtheria, tetanus, polio, neisseria meningitidis C
what are some non routine vaccines at birth
tuberculosis hep B (if mother is positive)
what are some vaccines that travellers may need
hepatitis A, typhoid, neisseria meningitidis serogroups (A, C, W135, Y), cholera, yellow fever, Japanese encephalitis, rabies
what are temporary contra-indications of vaccination
- febrile illnesses (illnesses with fevers)
- pregnancy (cannot be given live attenuated vaccines)
what are some permanent contra-indications of vaccination
- allergy
- immunocompromised (cannot be given live attenuated)
what is herd immunity
vaccinated individuals less likely to be a source of infection to others
this reduces risk of unvaccinated individuals being exposed to infection
what is antigenic shift
- a challenge facing vaccines
- co-infection of host with the virus allows genetic reassortment that give rise to novel antigenically distinct virus particles
- antigenic drift arises from point mutations
what is the cold chain network
purpose of vaccine ‘cold chain’ is to maintain product quality from the time of manufacture until the point of administration by ensuring vaccines are stored and transported within WHO recommended temperature ranges
what is a conjugate vaccine
- the antigen is the carbohydrate capsule
- carbohydrates are poor antigens (do not stimulate immune system as broadly as protein antigens), especially in babies
- conjugation of the carbohydrate to a protein carrier makes them more effective
- e.g streptococcus pneuomoniae
what vaccines are there for cancer
- HPV is linked to 100% of all cervical cancers
