(Last updated 9/24/2015; last reviewed 9/24/2015)
HIV testing shows whether a person is infected with HIV. HIV stands for human immunodeficiency virus. HIV is the virus that causes AIDS (acquired immunodeficiency syndrome). AIDS is the most advanced stage of HIV infection.
HIV testing can detect HIV infection, but it can’t tell how long a person has been HIV infected or if the person has AIDS.
Knowing your HIV status can help keep you—and others—safe.
If you are HIV negative:
Testing shows that you don’t have HIV. Continue taking steps to avoid getting HIV, such as using condoms during sex. For more information, read the AIDSinfo fact sheet on HIV prevention.
If you are HIV positive:
Testing shows that you are infected with HIV, but you can still take steps to protect your health. Begin by talking to your health care provider about antiretroviral therapy (ART). ART is the use of HIV medicines to treat HIV infection. People on ART take a combination of HIV medicines every day. ART helps people with HIV live longer, healthier lives. ART also reduces the risk of sexual transmission of HIV. Your health care provider will help you decide when to start ART and what HIV medicines to take.
The Centers for Disease Control and Prevention (CDC) recommends that everyone 13 to 64 years old get tested for HIV at least once and that people at high risk of infection get tested more often.
Factors that increase the risk of HIV infection include:
CDC recommends that all pregnant women get tested for HIV as early as possible during each pregnancy. Women who are planning to get pregnant should also get tested.
Women with HIV take HIV medicines during pregnancy and childbirth to reduce the risk of mother-to-child transmission of HIV. HIV medicines used as recommended during pregnancy can reduce the risk of mother-to-child transmission of HIV to less than 1%. For more information, read the AIDSinfo fact sheet on Preventing Mother-to-Child Transmission of HIV.
There are several HIV tests. Some are used for HIV screening and others for follow-up testing if a screening test result is HIV positive.
HIV screening tests
The HIV antibody test is the most common HIV screening test. The test checks for HIV antibodies in blood, urine, or fluids from the mouth. HIV antibodies are disease-fighting proteins that the body produces in response to HIV infection.
The time period from infection with HIV until the body produces enough HIV antibodies to be detected by an HIV antibody test is called the window period. Most people develop HIV antibodies within 3 months after they are infected with HIV. But the window period can vary depending on the HIV test used. In general, anyone who has a negative result on an HIV antibody test within 3 months of a possible exposure to HIV should have the test repeated in 3 months.
The HIV antigen/antibody test can detect both HIV antigen (a part of the virus) and HIV antibodies in blood. An antigen/antibody test can detect HIV infection before an HIV antibody test.
Follow-up HIV tests
A positive result on an HIV screening test must always be confirmed by a second HIV blood test. The following tests are used to confirm a positive result on an HIV screening test:
It usually takes a few days to a few weeks to get results of an HIV test. Some rapid HIV antibody tests can produce results within 30 minutes.
There are two HIV tests approved by the U.S. Food and Drug Administration (FDA) for home use.
The first test is a home collection kit, which involves pricking the finger for a blood sample, sending the sample to a lab for testing, and then calling the lab for results as early as the next business day. If the result is positive for HIV, the lab testing includes a follow-up test to confirm the initial HIV-positive test result. Test results include the follow-up test.
The other approved home use test comes with a test stick and a tube with a testing solution. The test stick is used to swab the gums to get a sample of oral fluids. To get results, the test stick is inserted into the test tube. Test results are ready in 20 minutes. A positive result on this home HIV test must always be confirmed by additional HIV testing performed in a health care setting.
HIV testing can be confidential or anonymous.
Confidential testing means that your HIV test results will include your name and other identifying information, but only people allowed to see your medical records will see your test results. HIV-positive test results may be reported to local or state health departments to be counted in statistical reports. Health departments remove all personal information (including names and addresses) from HIV test results before sharing the information with CDC. CDC uses this information for reporting purposes and does not share this information with any other organizations.
Anonymous testing means you don’t have to give your name when you take an HIV test. When you take the test, you receive a number. To get your HIV test results, you give the number instead of your name.
Your health care provider can give you an HIV test. HIV testing is also available at many hospitals, medical clinics, community health centers, and AIDS service organizations.