HIV and AIDS: Strategies for ControlAbout This Hardback The human immunodeficiency virus (HIV) is a type of retrovirus that causes a spectrum of conditions called acquired immunodeficiency syndrome (AIDS). HIV damages the immune system and thus interferes with the body's ability to fight infection and disease. It is spread primarily through unprotected sex, but also by contaminated blood transfusions, hypodermic needles, and from mother to child during pregnancy, delivery, or