HIV Medicine

Human Immunodeficiency Virus (HIV)

HIV stands for “human immunodeficiency virus.” It’s the virus that causes AIDS (acquired immunodeficiency syndrome). HIV is passed from person to person through sexual contact, blood exposure, childbirth, or breastfeeding.

HIV is a retrovirus, a virus that contains enzymes (proteins) that can turn RNA, its genetic material, into DNA. It’s called a retrovirus because this is the converted (transcribed) into RNA. After infection, HIV RNA gets turned into DNA by the reverse transcriptase enzyme. The DNA is then inserted into the DNA of human cells. That DNA can then either be used to create new viruses, which infect new cells, or it can remain latent in long-lived cells, or reservoirs, such as resting CD4 cells. HIV’s ability to remain latent is what allows it to persist for life, even with effective treatment. It’s what has kept us from finding a cure.

When it’s not treated, HIV infection causes progressive damage to the immune system and is almost universally fatal. It is the world’s most serious pandemic (global epidemic), and there are no immediate prospects for either a cure or a preventive vaccine. Fortunately, treatment today is highly effective, and deaths from HIV disease are now mostly preventable in countries where therapy is available and affordable.