HIV stands for the Human Immunodeficiency VirusA small infective organism which is incapable of reproducing outside a host cell.. If you have been told you are HIV positive, it means that your body has come into contact with HIV and you have become infected with the virus. The virus infects and damages cells in your immune system known as CD4 cells (T4 cells), a type of white blood cell that makes up a major part of your immune system. HIV uses these cells to make copies of itself.
Over time, if your CD4 cells are damaged, your body is less successful at protecting you from bugs and germs that can lead to infection or illness. HIV treatments can help you to stay well for longer. (See page 24 for more information about HIV treatments.)
When the immune system has been severely damaged by HIV infection, AIDS can occur. However, HIV and AIDS are two different things. AIDS stands for Acquired Immune Deficiency Syndrome. HIV can lead to AIDS when the immune system has been damaged to such an extent that it is vulnerable to other infections and diseases. These infections and diseases are called ‘opportunistic’ infections. The organisms that cause common AIDS defining illnesses are usually controlled by a healthy immune system. Many opportunistic infections are treatable or preventable.
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