HIV is a virus that attacks the immune system. For a long time, a person with HIV infection may feel well, and then face the so-called opportunistic diseases (tuberculosis, pneumocystis pneumonia, oncological diseases, and so on), the disease passes into the stage of AIDS (human acquired immunodeficiency syndrome), and the person may die. If a person is diagnosed with HIV in a timely manner, he is registered and regularly takes antiretroviral therapy, then the stage of AIDS does not occur in him and he will live as long as he was measured at birth.