What Is HIV? Understanding Causes, Symptoms, Treatments and More
Medically Reviewed by Dr. Samantha Miller, MBChB
Human immunodeficiency virus, more commonly known as HIV, is a virus which, without treatment, leads to deterioration of your body’s immune system to a point where your body has trouble fighting off mild infections. When your immune system has become severely damaged after a prolonged period with HIV, it’s known as acquired immune deficiency syndrome, or AIDS.
HIV is a blood-borne retrovirus that infects specific cells in the human immune system called CD4 T cells. CD4 cells normally play an important role in your immune system. There, they’re responsible for detecting harmful pathogens like bacteria and viruses so your body can begin fighting off those pathogens.
There’s no cure for HIV, and once you contract it, the virus will remain in your body for life. Over time, if left untreated, HIV can progressively damage your immune system to a point where you become susceptible to AIDS-defining illnesses — infections and conditions that wouldn’t normally make you sick if your immune system was functioning typically.