HIV (human immunodeficiency virus) is the virus that causes AIDS. This virus is passed from one person to another through blood-to-blood and sexual contact. In addition, pregnant women living with HIV can transmit the virus to their baby during pregnancy or delivery, as well as through breast-feeding. People with HIV have what is called HIV diagnosis. If untreated, these people will develop AIDS as a result of their HIV infection. AIDS stands for acquired immunodeficiency syndrome. A person living with HIV receives a diagnosis of AIDS after developing one of the CDC-defined AIDS indicator illnesses, (opportunistic infection.) One who is living with the virus and who has not had any serious illnesses also can receive an AIDS diagnosis on the basis of certain blood tests that measures their CD4+ counts (illness fighting white blood cells). A CD4+ count of less than 200 indicates a severely damaged immune system and an AIDS diagnosis. A positive HIV test result does not mean that a person has AIDS. A diagnosis of AIDS is made by a physician using certain clinical criteria. Also, once a person is diagnosed with AIDS, they will always be considered to have AIDS, regardless of clinical changes later on. For example, if a person has HIV and a CD4 count below 200, they are considered to have AIDS. If their CD4 count later goes back to above 200, they are still considered to have AIDS.
HIV can weaken the immune system to the point that it has difficulty fighting off certain infections. These types of infections are known as “opportunistic” infections because they take the opportunity a weakened immune system gives to cause illness. Many of the infections that cause problems or may be life threatening for people with AIDS, are usually controlled by a healthy immune system. The immune system of a person with AIDS is weakened to the point that medical intervention may be necessary to prevent or treat serious illness. Today there are medical treatments that can slow down the rate at which HIV weakens the immune system. There are other treatments that can prevent or cure some of the illnesses associated with AIDS. As with other diseases, early detection offers more options for treatment and preventative care.