The full form of AIDS is Acquired Immune Deficiency Syndrome. AIDS is the most advanced stage of HIV (human immunodeficiency virus) infection. HIV is a virus that attacks the bodys immune system, making a person more vulnerable to other infections and diseases. If HIV is not treated, it can lead to AIDS. AIDS is diagnosed when the CD4 T cell count falls below 200 or when a person has an AIDS-defining complication, such as a serious infection or cancer. Someone with AIDS can experience a variety of health conditions, including thrush, pneumonia, tuberculosis, skin diseases, cytomegalovirus, and toxoplasmosis. There is currently no effective cure for AIDS, but with proper medical care, HIV can be controlled, and people with HIV who get effective HIV treatment can live long, healthy lives and protect their partners.