What Is AIDS? The Basics

Key points
- AIDS is short for acquired immune deficiency syndrome.
- There is no cure, but anti-HIV drugs keep HIV in check.
- You can't get HIV from a toilet seat or from touching an infected person.
- It kills an important kind of blood cell - the CD4 T lymphocyte, or T cell.
What Is AIDS?
AIDS is short for acquired immune deficiency syndrome. AIDS is a disease that slowly destroys the body's immune system. Without these important defenses, a person with AIDS can't fight off germs and cancers.
HIV is the virus that causes AIDS. It kills an important kind of blood cell - the CD4 T lymphocyte, or T cell. These T cells are the quarterbacks of the immune system. As they die off, the body becomes more and more vulnerable to other diseases. Germs take this opportunity to invade the body. The diseases they cause are called opportunistic infections (OIs for short). When people with HIV get these infections - or when their CD4 T-cell levels get too low - they have AIDS.
Usually it takes many years for HIV to weaken the body's immune system to the point of AIDS. Anti-HIV drugs help prevent this. Even when a person already has AIDS, the drugs can help a person get better.
Anti-HIV drugs let many people with HIV infection live healthy lives. Combinations of these powerful medicines work very well, but they often have serious side effects, such as vomiting, diarrhea, and fatigue. And people with HIV have to keep taking these drugs every day for the rest of their lives. Ask anyone who's taking these "drug cocktails" - it's best to avoid getting HIV in the first place.
AIDS is a worldwide epidemic. Most cases are in Africa, but the disease is spreading most rapidly in Eastern Europe and Asia. Even if a cure were found tomorrow, AIDS will be the most deadly disease ever to plague mankind.
What Causes It?
HIV - human immunodeficiency virus - causes AIDS. HIV infection is for life. There is no cure, but anti-HIV drugs keep HIV in check. Unfortunately, 95% of the world's HIV infected people cannot afford this medicine.
There are a few people who say HIV does not cause AIDS. Some are scientists, but none of them are AIDS experts. They offer only false hope and no answers. Overwhelming medical and scientific evidence shows that HIV is the AIDS virus. Every major health organization in the world says that HIV is a killer.
There are two main types of HIV - HIV-1 and HIV-2. HIV-2 is rare outside Africa.
You can't catch HIV unless another person's body fluids - blood, semen, or vaginal secretions - enter your bloodstream. This can happen through the tip of the penis, through the vagina, through the rectum, or through an open wound.
HIV is spread
- By having sex without a condom. Vaginal and anal sex carry a high risk. The risk of getting HIV from oral sex is low.
Written and revised by
David Cohen, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
health.am provides general information, not medical advice. Always consult a qualified health professional about your own health.
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