HIV stands for human immunodeficiency virus and it weakens the body’s immune system (your defense against infections). It is the virus that causes AIDS.
The virus may be passed from one person to another when infected blood, semen or vaginal secretions come in contact with an uninfected person’s broken skin or mucous membranes. (A mucous membrane is wet, thin tissue found in certain openings to the human body, including the mouth, eyes, nose, vagina, rectum, and the opening of the penis.)
Additionally, an infected pregnant woman can pass HIV to her unborn baby during pregnancy, delivery or through breast-feeding.