Hiv is a virus. Its not very smart but it is clever. It can live in the body and replicate for years before any symptoms occur. This is why if you have sex without a condom you should get tested. In the 1980's many people died from AIDS and doctors basically told them to go home and get their affairs in order. It was in almost all cases fatal. The HIV virus attacks CD4 or helper cells by basically enering into the cell and changing the genetic makeup. This creates a cell which is killing itself.
As the virus continues to invade these cells damage to the immune system starts. A person at first may notice little things in the first few years. Changes in the way they feel, tired and they may notice their fingernails or toenails becoming brittle. As the virus continues to replicate eventually the CD4 count will fall below 200 and this is when an Aids diagnosis is given. Usually the person may be very sick at this time with either thrush and night sweats, weight loss and stiffness in the neck.The body at this point is giving in to the virus and the virus has all but destroyed the immune system.
Opportunistic Infections are infections which a normal bodies immune system may be able to fight off. In my case I developed Crytococcal menengitis, a fatal disease if not treated immediately. In most underdeveloped countries Crytococcal Menengitis kills the majority of AIDS patients who get it. Its not a pretty disease and can cause lasting cogntive impairments to the sufferer even after sussesful treatment. This is why testing is important. By becoming tested early someone with the HIV virus can still live a normal life if theytake medication to treat the virus. Without medication or knowledge that someone is HIV positive the damage can be done without even knowing it. Get tested and increase your chances of living a full and disease free life.