1. 1 and 1.2 Introduction and aims

1.1 Introduction

Section 1 starts with information about your body and the way your immune system fights infections.

• HIV is a virus.
• It is also a virus that attacks the immune system.
• Our immune system is the main way our body fight infections.
• But when our immune system tries to fight HIV, the virus steadily becomes stronger. As this happens, without HIV treatment (called ART), our immune system steadily becomes weaker.

1.2 Aims for this section

Reading section 1 will give you a basic understanding of the following.

• The ways a scientist or doctor understands the immune system.
• CD4 cells, CD4 tests and what they mean.
• How the CD4 count is used to monitor HIV infection.
• Use of CD4 count in treatment decisions and guidelines.

Last updated: 1 January 2023.