Unit 3 (K 7/8) - Immunisation and Clinical Trials of Vaccines & Drugs

Question 1

What is immunisation?

Answer 1

The process by which a person develops immunity to a disease causing organism (pathogen).

Question 2

How are B lymphocytes important for immunisation?

Answer 2

Vaccines use antigens from infectious pathogens, leading to the creation of memory cells.

Question 3

What are the 4 forms of antigens which may be present in a vaccine

Answer 3

1. Antigens from infectious pathogens
2. Parts of pathogens
3. Weakened pathogens
4. Inactivated pathogen toxins

Question 4

What is an adjuvant?

Answer 4

A substance that makes a vaccine more effective, so enhancing immune response.

Question 5

What is herd immunity?

Answer 5

This occurs when a large percentage of the population is immunised, reducing the spread of disease when herd immunity threshold is met.

Question 6

How are non-immune individuals protected when herd immunity threshold has been met?

Answer 6

There is a lower probability that they will come into contact with infected individuals.

Question 7

Explain the disadvantage of antigenic variation

Answer 7

This occurs when pathogens evolve and change their antigens. This means that memory cells are no longer effective against them.

Question 8

Why are vaccines and drugs put through clinical trials?

Answer 8

To establish their safety and effectiveness before licensed for use.

Question 9

Name the 3 protocols used in clinical trials

Answer 9

1. Randomised
2. Placebo-controlled
3. Double-blind

Question 10

What is the purpose of randomisation during clinical trials?

Answer 10

It reduces bias (by minimising the effects of factors such as age and gender).

Question 11

What is the purpose of placebo-controlled during clinical trials?

Answer 11

To increase the validity of results and ensures valid comparisons.

Question 12

What is the purpose of the double-blind protocol during clinical trials?

Answer 12

To eliminate bias.

Question 13

Why is group size important during clinical trials?

Answer 13

It is important that group size is large to increase the reliability of the results. This can also reduce experimental error and increase statistical significance.

Question 14

What is the double-blind protocol?

Answer 14

Where neither the subject nor the researchers know whether the subject is getting the vaccine or the placebo.