How does HIV affect the body?
HIV attacks and kills crucial immune system cells, known as T-helper cells. Without T-helper cells (which kill cells that have been infected with germs) many other immune system cells cannot not work properly, including B-cells that make antibodies. A person infected with HIV may not show any symptoms for years. But untreated, the number of T-helper cells steadily drops. Eventually, the numbers fall so low that the risk of infection greatly increases, and the symptoms of AIDS appear.