Immunisation Flashcards
What are the 3 main aims of immunisation
- Primary prevention - helping healthy people avoid disease
- Interrupt transmission of disease
- Secondary prevention - prevent consequences of disease
When was the smallpox vaccine created and when was the last known case of smallpox?
Vaccine created in 1940s
Last known case of Smallpox = 1977
Describe what is meant by ACTIVE immunity
exposure to antigens either in environment or via artificial vaccine
What is PASSIVE immunity and how can it be achieved?
Transfer of pre-formed immunoglobulins
From mother to unborn baby
From person to person OR animal to person
What injections can be given to demonstrate passive immunity?
- Human Immunoglobulin (e.g. HepB, rabies)
- Anti-toxins (e.g. diptheria)
What are the main advantages and disadvantages of giving passive immunity via injections?
ADV: - Rapid action - Outbreak control - Can be used if contraindication to active vaccination
DISADV:
- Short-term protection
- Hypersensitivity reaction
- Expensive
Describe the process of herd immunity
Individuals who are not vaccinated are protected by having a high percentage of people in the population who are vaccinated
Describe how organisms in live vaccines are manipulated to make sure they do not cause disease in humans
Organisms are put in a variety of animal tissues to specialise them for causing disease in that host
=> less able to cause disease in human tissue, however they can still replicate and cause immune response
What are the different subtypes of inactivated vaccines?
- Suspensions of killed organisms
- Subunit vaccines
- Conjugate vaccines
What organisms can be found in live attenuated vaccines?
measles, mumps, rubella, varicella rotavirus zoster flu
Give examples of inactivated vaccines which contain killed organisms
whole cell pertussis (whooping cough)
whole cell typhoid
What organisms are found in inactivated subunit vaccines?
Diptheria Toxoid
Tetanus Toxoid
What infection cannot be protected against by herd immunity?
Tetanus
What components make up an inactivated conjugated vaccine?
polysaccharide attached to immunogenic proteins
e.g. Hib, MenC
When are vaccines contraindicated?
- Patient has known anaphylaxis to vaccine component
- egg allergy (found in yellow fever and flu vaccines)
- severe latex allergy
- Acute or evolving illness (wait until settled)