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Testing HIV Positive – Do I Have AIDS?

I tested HIV positive. What does this mean? Does it mean I have AIDS?

A positive HIV test result means that you are infected with HIV (Human Immunodeficiency Virus), the virus that causes AIDS (Acquired Immune Deficiency Syndrome). Being infected with HIV does not mean that you have AIDS right now. However, if left untreated, HIV infection damages a person’s immune system and can progress to AIDS.

What is AIDS?

AIDS is the most serious stage of HIV infection. It results from the destruction of the infected person's immune system. Your immune system is your body's defense system. Cells of your immune system fight off infection and other diseases. If your immune system does not work well, you are at risk for serious and life-threatening infections and cancers. HIV attacks and destroys the disease-fighting cells of the immune system, leaving the body with a weakened defense against infections and cancer.

Which disease-fighting cells does HIV attack?

CD4 cells are a type of white blood cell that fights infections. They are also called CD4+ T cells or CD4 T lymphocytes. A CD4 count is the number of CD4 cells in a sample of blood. When HIV enters a person's CD4 cells, it uses the cells to make copies of itself. This process destroys the CD4 cells, and the CD4 count goes down. As you lose CD4 cells, your immune system becomes weak. A weakened immune system makes it harder for your body to fight infections and cancer.

How will I know if I have AIDS?

AIDS is not a diagnosis you can make yourself; it is diagnosed when the immune system is severely weakened. If you are infected with HIV and your CD4 count drops below 200 cells/mm3, or if you develop an AIDS-defining condition (an illness that is very unusual in someone who is not infected with HIV), you have AIDS.

What are the AIDS-defining conditions?

In December 1992, the Centers for Disease Control and Prevention (CDC) published the most current list of AIDS-defining conditions*. The AIDS-defining conditions are: People who are not infected with HIV may also develop these diseases; this does not mean they have AIDS. To be diagnosed with AIDS, a person must be infected with HIV.

What is HIV treatment?

HIV treatment is the use of medications to keep an HIV infected person healthy. Treatment can help people at all stages of HIV disease. Although anti-HIV medications can treat HIV infection, they cannot cure HIV infection. HIV treatment is complicated and must be tailored to you and your needs.

The Fact Sheets in this series provide information about HIV treatment, including when to start medication, which medications are used, how to know if treatment is working, and what can be done if your treatment is not working.

For more information:

Contact your doctor or an AIDSinfo Health Information Specialist at 1-800-448-0440 or

*CDC. 1993 Revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR 1992;41 (no. RR-17).

This information is based on the U.S. Department of Health and Human Services' Guidelines for the Use of Antiretroviral Agents in HIV-Infected Adults and Adolescents (available at

   Reviewed: October 2004