Acquired immunodeficiency syndrome (AIDS) is a chronic, potentially life threatening condition caused by the Human immunodeficiency virus (HIV). HIV virus is of 2 types namely HIV 1 & HIV 2 of which HIV 2 is less transmissible & less likely to progress to AIDS. By damaging your immune system, HIV interferes with your body’s ability to fight infection and disease. It can spread through sexual contact or blood by sharing infected needles or from mother to child during pregnancy, childbirth or breast-feeding. It may take years before HIV weakens your immune system & causes full blown AIDS. Anti-viral treatment has reduced the death rate due to AIDS. This is a quantitative test that gives the viral load of HIV 1 in your body. This is useful for monitoring response to treatment. In addition, it also indicates the immune status. An HIV positive individual with CD4 count of 200 or less is at risk of developing AIDS.