Spread of infection: sexually transmitted infections

Teaching Time: 50min

Target Group: Key Stage 3

Curriculum Links:

Science: Working scientifically; Experimental skills and investigations, Analysis and evaluation

PSHE: Core Theme 1 - Health and Wellbeing

GCSE: Health and social care

Learning Objectives:

All students will:

  • understand that infection can be spread easily through sexual contact.
  • understand what they can do to protect themselves against STIs.

Most students will:

  • understand that non-barrier forms of birth control do not protect against STI.

Some students will:

  • know that not everyone with an STI has symptoms.
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Sexually transmitted infections are on the increase, particularly amongst the young adult population. This section aims to teach students how sexual activity can lead to the spread of microbes and disease. Students observe how easily potentially harmful microbes can transfer to the people you care about without either of you knowing.

Activities include:

  • A chemical experiment to see how many people can be infected unknowingly by unprotected sexual intercourse (exchange of body fluid) and how we can prevent this from happening.
  • A comic strip where two characters make some good and bad decisions, allowing students to discuss just how wise these decisions are and how relevant they are to them.

This video gives an example of how to conduct the main experiment on the transmission of STIs.


This lesson has been developed in partnership with the Studies in Adolescent Sexual Health (SASH) research group at Coventry University www.healthinterventions.co.uk

Coventry university SASH





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DISCLAIMER: e-Bug was developed for use in schools pre-COVID-19 and so some activities may require modification based on your school’s distancing guidelines.

Please use your judgement and tell us how you have modified the activities, or if you would like to discuss some ideas, contact e-Bug@phe.gov.uk

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