Human Immunodeficiency Virus (HIV) is the virus that causes Acquired Immune Deficiency Syndrome (AIDS.) HIV is an infectious agent that invades and disables a person’s immune system, the body’s natural defense against disease. The only way a person can become infected with HIV is through exposure to HIV‑infected blood or other infectious body fluids including semen and vaginal fluid. HIV is primarily transmitted through unprotected sex (sex without a condom or other barrier use) and/or injection drug use (sharing of contaminated syringes and other injection equipment). Children born to HIV-infected mothers and rarely, health care workers caring for HIV-infected patients, and recipients of blood transfusions or organ donations can also be at risk. There is no cure for HIV infection. HIV‑infected persons who do not receive appropriate medical care may become ill and be diagnosed with an AIDS defining condition.
AIDS is a syndrome, or collection of signs and symptoms, that is attributed to the natural course of HIV infection. The Centers for Disease Control and Prevention has classified a total of 27 different diagnoses and conditions as AIDS‑defining illnesses. Once diagnosed with AIDS, many people can subsequently begin, resume, or modify HIV treatment regimens and maintain or return to productive, relatively healthy lifestyles. Without adequate treatment, AIDS is a fatal condition.
For more information about HIV/AIDS go to http://aids.gov/basic/index.html or http://www.cdph.ca.gov/programs/AIDS.