Once transformed, the viral DNA will travel into the T-cell's nucleus and sews itself to the cell's genetic material (a process similar to placing a "bug" in a computer software program). At this point, if the T-cell is activated, instead of performing T-cell functions, it will start producing and shedding new virus

At this stage, several things can happen. The new virus ("provirus") can remain inactive for a long time without triggering the reproduction of virus, or it can divide into two pro viruses (mitosis), or it can start producing new virus that will bud off from the T-cell wall, eventually destroying the T-cell.

Due to its method of reproduction, HIV is particularly devastating to the immune system. In the process of reproducing, the virus destroys increasing numbers of T-cells. The coordinator cells of an important part of the immune system are annihilated, leaving the body open to opportunistic infections.