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HIV
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enzyme-linked immunosorbent assay test antiretroviral drug T cell infected with HIV
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Transmission electron micrograph of HIV-1 virus particles (red) budding and replicating from a segment of a chronically infected H9 cell (blue). Particles are in various stages of maturity; arc/semi-circles are immature particles that have started to form but are still part of the cell. Immature particles slowly change morphology into mature forms and exhibit the classic "conical or spherical-shaped core." Image captured at the NIAID Integrated Research Facility (IRF) in Fort Detrick, Maryland. (Human Immunodeficiency Virus, Acquired Immune Deficiency Syndrome, AIDS)
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HIV

virus
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Also known as: human immunodeficiency virus
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human immunodeficiency virus

News •

151 new HIV cases diagnosed in Singapore in 2024; first time the number fell below 200 since 1998 • May 20, 2025, 12:26 AM ET (Straits Times)
South Africa says Trump's aid cuts stripped more than 8,000 health workers from its HIV program • May 15, 2025, 12:13 PM ET (AP)
UNAIDS to slash workforce by more than half as funding by US and other big donors disappears • May 6, 2025, 11:47 AM ET (AP)

HIV, retrovirus that attacks and gradually destroys the immune system, leaving the host unprotected against infection. HIV is classified as a lentivirus (meaning “slow virus”). Persons who are infected with HIV often die from secondary infections or cancer. AIDS is the final stage of HIV infection. For detailed information on HIV and disease, see AIDS.

This article was most recently revised and updated by Kara Rogers.