What does vaccination involve?

Vaccination involves introducing antigens into the body to stimulate an immune response without causing disease.

Explain how vaccines provide long-term immunity.

Vaccines stimulate the production of memory cells, which remain in the body and enable a rapid secondary response upon subsequent exposure to the pathogen.

How can vaccination programmes prevent epidemics?

Vaccination programmes prevent epidemics by reducing the number of susceptible individuals in a population, limiting pathogen spread.

What are routine vaccinations?

Routine vaccinations are given to populations according to a schedule to prevent common communicable diseases.

Why might vaccines need to be changed over time?

Vaccines may need to be changed due to antigenic variation in pathogens such as influenza, where surface antigens mutate.

OCR A-Level Biology H420

Cell Structure

Topic overview Microscopy, slide preparation and staining Biological drawings, magnification and resolution Eukaryotic cell ultrastructure The secretory pathway and the cytoskeleton Prokaryotic and eukaryotic cells compared

Biological Molecules

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Communicable Diseases, Disease Prevention and the Immune System

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Communicable Diseases, Disease Prevention and the Immune System

Vaccination

2 things to know
Components 02 and 03

Overview

What a vaccine contains and how it produces long-term immunity, herd immunity and the prevention of epidemics, and why programmes change over time.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

What is herd immunity and why do vaccination programmes aim to achieve it?

Process

Explain how vaccination protects populations.

Questions from this subtopic

Each one with the model answer underneath.

1
What does vaccination involve?
Model answer
Vaccination involves introducing antigens into the body to stimulate an immune response without causing disease.
2
Explain how vaccines provide long-term immunity.
Model answer
Vaccines stimulate the production of memory cells, which remain in the body and enable a rapid secondary response upon subsequent exposure to the pathogen.
3
What is herd immunity and why do vaccination programmes aim to achieve it?
Model answer
Herd immunity occurs when a large proportion of a population is immune, protecting those who cannot be vaccinated by reducing pathogen transmission.
4
How can vaccination programmes prevent epidemics?
Model answer
Vaccination programmes prevent epidemics by reducing the number of susceptible individuals in a population, limiting pathogen spread.
5
What are routine vaccinations?
Model answer
Routine vaccinations are given to populations according to a schedule to prevent common communicable diseases.
6
Why might vaccines need to be changed over time?
Model answer
Vaccines may need to be changed due to antigenic variation in pathogens such as influenza, where surface antigens mutate.

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