HIV can be caused by blood transfusions, sharing needles, having sex, or during pregnancy. This virus cannot be transmitted through ordinary contact such as hugging or shaking hands with someone who has the virus. It also cannot be transmitted through the air, water, or insect bites.Once the HIV virus is inside of you it destroys your CD4 cell, these are a type of white blood cell that help your body fight disease, as more of these cells are killed your immune system weakens. We your CD4 cell count drops below about 200 your HIV will progress to AIDS or you will experience an AIDS-Defining Illness.
Immune cells involved in immune response
How virus replicates
Binding and Fusion: This is the process by which HIV binds to a specific type of CD4 receptor and a co-receptor on the surface of the CD4 cell. This is similar to a key entering a lock. Once unlocked, HIV can fuse with the host cell (CD4 cell) and release its genetic material into the cell.
Reverse Transcription: A special enzyme called reverse transcriptase changes the genetic material of the virus, so it can be integrated into the host DNA.
Integration: The virus’ new genetic material enters the nucleus of the CD4 cell and uses an enzyme called integrase to integrate itself into your own genetic material, where it may “hide” and stay inactive for several years.
Transcription: When the host cell becomes activated, and the virus uses your own enzymes to create more of its genetic material—along with a more specialized genetic material which allows it make longer proteins.
Assembly: A special enzyme called protease cuts the longer HIV proteins into individual proteins. When these come together with the virus’ genetic material, a new virus has been assembled.Budding: This is the final stage of the virus’ life cycle. In this stage, the virus pushes itself out of the host cell, taking with it part of the membrane of the cell. This outer part covers the virus and contains all of the structures necessary to bind to a new CD4 cell and receptors and begin the process again.