HIV is especially difficult for the body to deal with. This is because the cells that the virus uses to reproduce itself are the cells that the body uses to fight a viral infection.

These two factors are like a dog chasing its tail!

• HIV infection makes the body produce more CD4 cells to fight this new virus
• These new cells provide more target cells for HIV to infect and reproduce
• The body responds by making even more cells to fight the new virus

Most people develop immune cells that specifically try to fight the virus. These are called HIV-specific CD4 cells (or T4 cells). However, they get worn out and disappear in most people within 6 months after infection.

Then the virus continues infection other CD4 cells. Without treatment, usually over many years, the rest of the immune system is worn down.

This details of the immune response are very complicated.

The main point is that HIV makes the immune system go into overdrive, producing more and more cells.

Over time the immune system loses out. This is why your CD4 count drops over time.

HIV infected cells die more quickly. Once they are active, they only live for 1-2 days instead of 3-4 days. HIV infected cells also signal to infected cells to die more quickly. Therefore, HIV doesn’t need to infect every cell to cause them to die.

ARV treatment blocks HIV from reproducing, and returns your immune system back to an almost normal state.

HIV and the immune system before ARV treatment

HIV and the immune system after ARV treatment