skip to content

HIV/AIDS Glossary

Acquired Immunodeficiency Syndrome (AIDS)

A disease of the immune system due to infection with HIV. HIV destroys the CD4 T lymphocytes (CD4 cells) of the immune system, leaving the body vulnerable to life-threatening infections and cancers. Acquired immunodeficiency syndrome (AIDS) is the most advanced stage of HIV infection. To be diagnosed with AIDS, a person with HIV must have an AIDS-defining condition or have a CD4 count less than 200 cells/mm³ (regardless of whether the person has an AIDS-defining condition).

Related Term(s): Acute HIV Infection, AIDS Case Definition, Chronic HIV Infection, HIV Progression, Human Immunodeficiency Virus

Image(s):

(Click to enlarge)
Progression of HIV infection to AIDS illustrated with test tubes, CD4 cells, and virions.
Conditions that lead to an AIDS diagnosis

Search the Glossary

What's this?

Print

AIDSinfo Glossary App

Download Glossary