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What are HIV and AIDS?

A young girl sitting in a café is sending a text message about HIV/AIDS to her friendHIV (human immunodeficiency virus) is the virus that causes AIDS (acquired immune deficiency syndrome). AIDS is a disease of the immune system for which there is treatment, but no cure, at the present time. The virus (HIV) and the disease it causes (AIDS) are often linked and referred to as "HIV/AIDS."

HIV can be transferred between people if an infected person's blood or other bodily fluid comes in contact with the blood, broken skin, or mucous membranes of an uninfected person. In addition, infected pregnant women can pass HIV to their babies during pregnancy, delivery, and breastfeeding.

HIV destroys a certain kind of white blood cell that is crucial to the normal function of the human immune system. Loss of these CD4+ cells in people with HIV is a key predictor of the development of AIDS. Because of their compromised immune system, people with AIDS often develop infections of the lungs, brain, eyes, and other organs, and they frequently suffer dangerous weight loss, diarrhea, and a type of cancer called Kaposi's sarcoma.[*]

Some hopeful news is that, in recent years, HIV is no longer a death sentence, as it was when the epidemic began. This is largely because of treatment with HAART (highly active antiretroviral therapy), a combination of three or more antiretroviral medications that can suppress the virus and prevent or decrease symptoms of illness.

* Centers for Disease Control and Prevention, National Center for HIV, STD, and TB Prevention. What Is HIV? ( Atlanta, GA: CDC, DHHS. Retrieved June 2012
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