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Early HIV infection often causes no symptoms, and must be detected by testing a person's blood for the presence of antibodies—disease-fighting proteins—against HIV. These HIV antibodies generally do not reach levels high enough to detect by standard blood tests until one to three months following infection, and may take as long as six months. People exposed to HIV should be tested for HIV infection as soon as they are likely to develop antibodies to the virus.
When a person is highly likely to be infected with HIV and yet antibody tests are negative, a test for the presence of HIV itself in the blood is used. Repeat antibody testing at a later date, when antibodies to HIV are more likely to have developed, is often recommended.
After HIV infection occurs, it may be years before the virus destroys the immune system and serious infections and some cancers appear. At that point, the HIV infection has progressed to AIDS. New drug treatments can delay the effects of HIV/AIDS and are helping patients live longer. But the reality is that no medicine can cure AIDS or the virus that causes it, HIV. Once inside the body, HIV destroys immune system cells if not treated, with a progression to AIDS. AIDS remains a deadly epidemic worldwide.
A variety of types of tests are used to diagnose HIV/AIDS, including:
Clinical trials are research studies that evaluate a new medical approach, device, drug, or other treatment. As a Stanford Health Care patient, you may have access to the latest, advanced clinical trials.
Open trials refer to studies currently accepting participants. Closed trials are not currently enrolling, but may open in the future.