HIV (Human Immunodeficiency Virus) is a retrovirus that attacks the immune system of infected individuals and weakens their ability to fight off infections and diseases.

HIV is primarily transmitted through certain body fluids, including blood, semen, vaginal fluids, and breast milk. It can spread through unprotected sexual intercourse, sharing needles or syringes, and from an HIV-positive mother to her child during childbirth or breastfeeding.

Without proper medical treatment, HIV can progress to a more severe stage called AIDS (Acquired Immunodeficiency Syndrome). AIDS is characterized by a significant decline in immune function, leaving individuals vulnerable to opportunistic infections and cancers.