How HIV Causes Disease

CD4 T-cells (a type of white blood cell) are important to your body's defence against infections. This animation describes how your immune system is weakened by the HIV virus, which targets CD4 T-cells and leads to their gradual decline in number. Low to very low levels of CD4 cells put you at risk for 'opportunistic infections' that take advantage of the body's weakened immune system. To learn more visit