Immunisation Principles and Practice Flashcards
What are the types of immunisation?
- Active
- Passive
What is active immunisation termed?
Vaccination
What does vaccination produce?
Long-lasting protective immunity
What is passive immunisation?
Injection of antibodies
What do injections of immunoglobulins provide?
Short term protection against certain infections
What are injections of immunoglobulins useful in?
The management of immune disorders
How are injections of immunoglobulins obtained?
Pooled plasma, containing antibodies of certain prevalent pathogens
What can post-exposure management be used for?
- HBV
- VZV
- Tetanus
What is the main drawback of passive immunisation?
- The short acting effect it has
- The potential contamination with infected blood
Why is there potential for contamination with infected blood with passive immunisation?
As they are a blood product
What does vaccination aim to do?
Improve the adaptive immune response to antigens of a particular microbe so that the first infection produces a secondary immune response (IgG)
How long do vaccines last?
A long time, but may require booster responses
What features should an effective vaccine have?
- Safe
- Protective for a sustained period
- Induce the neutralising antibody whilst being biologically Stable
- Cheap
- Easy to produce
What are vaccines derived from?
Viruses or bacteria, or their antigenic components
What are the types of vaccines?
- Live
- Non-replicating
- Toxoids
What do live vaccines contain?
Strains of the pathogen where the pathogenicity has been removed (attenuated)
Give two examples of live vaccines
- BCG
- MMR
What is the problem with live vaccines?
- They can cause disease in immunocompromised patients
- Can’t be used during pregnancy
Why can’t live vaccines be used during pregnancy?
Due to the risk of foetal infection
What are non-replicating vaccines?
Can be either whole organisms, or fragmented containing their antigenic components
Give an example of a non-replicating vaccine that is a whole organism
Pertussis
Give an example of a non-replicating vaccine that is a fragmented organism containing their antigenic components
Capsular polysaccharide of streptococcus pneumonia
What can some non-replicating vaccines be conjugated with?
Proteins
Why are some non-replicating vaccines conjugated with proteins?
To increase the immunogenicity of the vaccine
What are toxoids?
Inactivated toxins of a pathogen
Are toxoids pathogenic?
No
Give two examples of common toxoid vaccines
- Diptheria
- Tetanus
What has to be given with vaccines in some scenarios?
Adjuvants
Why do vaccines sometimes have to be given with an adjuvant?
To enhance the response towards the vaccine by the immune system to proivde adequate immune cover
What is a vaccine adjuvant defined as?
A substance that will enhance the consequence of the immune response when administered simultaneously with the antigen
What can vaccine adjuvants be?
- Inorganic salts
- Delivery systems to APCs
- Bacterial products
Give an example of a vaccine adjuvant that is an inorganic salt?
Alum
Give two examples of vaccine adjuvants that are delivery systems to APCs
- Liposomes
- Polymers
Give an example of where a vaccine adjuvant that is a bacterial product is used?
In the BCG vaccine
How does a vaccine provide long term management?
By generating a memory in the immune system
How does vaccination provide a memory to the immune system?
Vaccination leads to B-cell stimulation and T-cell stimulation. B-cell stimulation leads to antibody production, and T-cell stimulation lead to affinity maturation, immunological memory, and cell mediated mechanisms, which all lead to immunity
What vaccines to all people in the UK receive?
- D-T-P
- HiB
- Oral Polio
- Meningococcal C
- MMR
- Booster D-T and Polio
- BCG
When is the D-T-P vaccine given?
1st dose at 2 months, 2nd dose at 3 months, 3rd dose at 4th months
When is the HiB vaccine given?
- 1st dose at 2 months
- 2nd dose at 3 months
- 3rd dose at 4th months
When is the Oral Polio vaccine given?
- 1st dose at 2 months
- 2nd dose at 3 months
- 3rd dose at 4th months
What kind of vaccine is D-T-P?
D and T are toxoid, P is killed bacteria
What kind of vaccine is HiB?
Conjugated capsular polysaccharide
What kind of vaccine is oral polio?
Live attenuated
When is the meningococcal C vaccine given?
2-4 months
What is the meningococcal C vaccine effective against?
Only A and C strains
When is the MMR vaccine given?
12-15 months
What kind of vaccine is the MMR?
Live attenuated
When is the booster D-T and polio vaccine given?
3-5 years, and 13-18 years
When is the BCG vaccine given?
10-14 years
What kind of vaccine is BCG?
Live attenuated M. Bovis
What is given in addition to the vaccines that all of the population have?
Selective programs for those at risk of certain diseases
Give an example of someone who may be at increased risk of certain diseases
A health care worker
What do all clinical vaccines carry?
Some degree of risk
What is the result of all clinical vaccines carrying some degree of risk?
It is vital with any vaccine that the risks are outweighed by the risk of disease
What must happen before vaccines are given?
- Extensive trials are used for vaccinations
- Any administrator of a vaccine should check the manufacturer’s instructions before administration
