Immunization and Prophylaxis Flashcards
What are the two divisions of artificial adaptive immunity?
- Passive: antibody transfer (immunoglobulins)
- Active: Vaccination so body produces own antibodies
What effect does immunological memory have on the production of antibodies?
- Both IgG and IgM antibodies synthesized much earlier in response to second exposure to pathogen
- Significantly higher production of total antibodies (IgG markedly raised)
How many doses are often required to build up significant immunological memory from a killed vaccine? From a live vaccine? Why is this?
- 3 for killed vaccine
- 1 for live vaccine
- Because the live vaccine will replicate while inside the host, requiring more antibodies to be produced to contain it. Killed vaccine doesn’t replicate
What are the different types of vaccinations?
- Live attenuated
- Inactivated (killed)
- Detoxified exotoxin
- Subunit vaccination
How is a detoxified exotoxin vaccine made?
- Isolate the toxin from the microorganism, treat with formalin: becomes a toxoid
- Give toxoid to patient
How are some subunit vaccinations made? (eg. hepatitis B vaccine)
- DNA segment coding for pathogen antigen (HBsAg) is removed, isolated and mixed with plasmids
- Inserted into yeasts for fermentation, then large amounts of antigen (HBsAg) collected
- Antigen given to patient
Describe the concept of herd immunity? What percentage of the population should have antibodies for it to be effective?
Herd immunity: immunize a significant portion of the population making them immune to the disease, this interrupts the transmission of the disease as the healthy people don’t spread it = much harder to spread
- Aim for 90-95% of pop. to be vaccinated / immune
As the incidence of a particular disease decreases significantly within a population what tends to happen to the vaccine?
Instead of being universally given the vaccine is only given to those in high risk groups / people likely to be exposed to the disease
What disease does the Bacille Calmette-Guerin (BCG) vaccine protect against?
Tuberculosis
As UK incidence of TB dropped largely in the UK, the BCG stopped being given universally in 2005
What do the pneumococcal vaccines protect against? What are the two different types?
The pneumococcus bacteria:
- Pneumonia septicaemia
- Meningitis
Adult and a child vaccine
What does the varicella zoster vaccine protect against? What type of vaccine is it?
- Chickenpox
- Live attenuated
What does the herpes zoster vaccine protect against? Which groups is it indicated in?
Shingles
Elderly patients (70-80 years)
What are the types of passive immunoglobulin transfers available?
- Human normal immunoglobulin (taken from other patients)
2. Disease specific immunoglobulin
When is a human normal immunoglobulin transfer indicated?
When the patient has immunoglobulin deficiencies
- Also indicated in some autoimmune disorders such as myasthenia gravis
When is a disease specific immunoglobulin transfer indicated?
When the patient has the infection, vastly improves their chance of fighting the infection
