Immunisation Flashcards Preview

Unit 4 Biology > Immunisation > Flashcards

Flashcards in Immunisation Deck (11)
Loading flashcards...
1
Q

How can vaccination immunity be developed?

A

By vaccination using antigens from infectious pathogens, so creating memory cells

2
Q

what can antigens used in vaccines be?

A

Inactivated pathogen toxins, dead pathogens, parts of pathogens and weakened pathogens

3
Q

What are antigen usually mixed with?

A

Adjuvant when producing the vaccine

4
Q

When does Herd immunity occur?

A

When a large percentage of a population is immunised.

5
Q

Why is establishing herd immunity important?

A

Reducing the spread diseases

6
Q

Why are non immune individuals protected?

A

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

7
Q

What does the herd immunity threshold depend on?

A

The type of disease, the effectiveness of the vaccine and the density of the population

8
Q

What are mass vaccination designed for?

A

To establish herd immunity to a disease

9
Q

When can difficulties arise with mass vaccination programmes?

A

When widespread vaccination is not possible due to poverty in the developing world, or when vaccines are rejected by a percentage of the population in the developed world

10
Q

What is antigenic variation ?

A

when some pathogens can change their antigens

11
Q

What can antigenic variation lead to?

A

Memory cells are not effective against them. Role and impact of antigenic variation in influenza