Vaccines

Question 1

Define variolation

Answer 1

Deliberate infection with smallpox

Question 2

What did Edward Jenner do?

Answer 2

Introduced a vaccine for small pox

Question 3

Define pathogenicity

Answer 3

Whether an infection turns into a disease

Question 4

Define transmissibility

Answer 4

How easy is it for a pathogen to move from one person to another

Question 5

Define heard immunity

Answer 5

When the proportion of immune individuals in a population reaches threshold, the spread of the disease to the non-immune population can be interrupted

Question 6

What happens the second time we see a pathogen?

Answer 6

Produce specific IgG antibodies over time
An adaptive immune system is able to recognise the pathogen and has produced memory specific/antigen-specific antibodies
Will not progress to disease, will clear the infection

Question 7

What is the basic concept of vaccines?

Answer 7

To deliver to the body part or all of the disease organism that imitates the pathogen but it is not pathogenic

Question 8

What are vaccines targets?

Answer 8

Antigenic components

Question 9

Name some types of vaccines

Answer 9

Live - attenuated vaccines
Inactivated
Recombinant sub unit
Toxoid
Conjugate polysaccharide-protein

Question 10

What is attenuated vaccines mean?

Answer 10

Evolve the pathogen so its so longer causes disease or kill it

Question 11

What are live attenuated vaccines and give examples?

Answer 11

Measles, Mumps and Rubella
Derived from wild or disease-causing, virus or bacteria are attenuated or weakened
The live attenuated vaccines must grow and replicate in the vaccinated person
Small dose of the bacteria or virus
Creates enough virus to stimulate an immune response

Question 12

What are the advantages of live-attenuated vaccines?

Answer 12

Cheap, adjuvants not required

Question 13

What are the disadvantages of live-attenuated vaccines?

Answer 13

Potential to cause pathology - some people are more susceptible than others (immunocompromised)
Stability - live - storage and handling

Question 14

What are adjuvants?

Answer 14

Added to the vaccine to help our immune systems recognise the pathogen better

Question 15

What are inactivated vaccines and give examples?

Answer 15

Hep A, Influenza and Pneumococcal polysaccharide
Produced by growing the bacteria or virus in culture media then inactivating it with heat and/or chemicals
Not alive and cannot replicate in the host, need larger doses of the antigen
Cannot cause disease from infection even in an immunodeficient person
In general the 1st dose does not produce protective immunity - only primes the immune system
Protective immunity after the 2nd and 3rd doses

Question 16

What are the advantages of inactivated vaccines?

Answer 16

Generally safer
Improved stability - no issues with the cold chain

Question 17

What are the disadvantages of inactivated vaccines?

Answer 17

Can be costly - inactivation and purification adding to costs
Hypersensitivity