human immunodeficiency virus [HIV]By admin / March 8, 2023 Human immunodeficiency virus, the virus which causes AIDS. There are two variants: HIV-1, and HIV-2. HIV-1 is by far the most common worldwide. See ‘subtype’ for more information. Related Articles: ZIP InitiativeZIP CoalitionsAbout InzypreGlossary: AIDSAcquired Immune Deficiency Syndrome. A collection of specific illnesses and conditions which occur because the body's immune system has been damaged by HIV.Glossary: antibodyA protein substance (immunoglobulin) produced by the immune system in response to a foreign organism. Many diagnostic tests for HIV detect the presence of antibodies to HIV in blood.