HIV Overview

HIV Testing

Last Reviewed: May 28, 2025

Key Points

  • HIV testing determines if a person has acquired HIV (human immunodeficiency virus). When untreated, HIV can progress to acquired immunodeficiency syndrome (AIDS).
  • Because HIV is often (as often as 40%) transmitted by people who are not aware they have it, testing is important to prevent HIV transmission. HIV testing is recommended for everyone aged 13 to 64 years as part of a routine health care exam.
  • More frequent HIV testing is recommended for people who are more likely to transmit or acquire HIV, including people who do not engage in safer sex practices, such as using condoms; those who inject drugs; and pregnant women.

 

What is HIV testing?

Testing for HIV determines if a person has acquired HIV. HIV is the virus that causes AIDS, which is the third and most advanced stage of HIV infection.

HIV testing can detect if you have HIV, but it cannot tell how long you have had HIV or what stage of HIV infection you are in. See The Stages of HIV Infection fact sheet to learn more about how HIV progresses when untreated.

Why is HIV testing important?

There are two reasons why HIV testing is important:

  • First, an estimated 15 percent of people with HIV in the United States are unaware they have HIV, and the Centers for Disease Control and Prevention (CDC) estimates that about 40 percent of new HIV diagnoses are transmitted by those who are not aware of their HIV status. Knowing your HIV status can help keep you—and others—safe.
  • Second, early identification and treatment of HIV is important to increase health and reduce related illnesses. Early and sustained treatment will help you live a long, healthy life.

If you are HIV negative:

A negative HIV test result shows that you do not have HIV. If you have certain risk factors, you need to continue taking steps, such as using condoms during sex, to avoid getting HIV. The chances of getting HIV may be higher for some people due to certain behaviors or situations. Examples of these individuals include:

  • People who have unprotected sex with multiple partners or with strangers (such as sex workers)
  • Health care workers who may come in contact with bodily fluids
  • People who travel to areas where HIV is common (such as sub-Saharan Africa)
  • Men who have sex with men (MSM)
  • People who inject drugs, specifically those who share needles

If you have certain risk factors for HIV, you can consider taking medicines to prevent HIV (called pre-exposure prophylaxis, or PrEP). For more information, read the HIVinfo fact sheets on The Basics of HIV Prevention and Pre-Exposure Prophylaxis.

If you are HIV positive:

A positive HIV test result shows that you have HIV, but you can still take steps to protect your health and the health of your partners. Begin by talking to your health care provider about HIV medicines, known as antiretroviral therapy (ART).

People on ART usually take a combination of oral HIV medicines (as a single pill or multiple pills) every day to treat HIV infection. In some cases, doctors prescribe long-acting injections instead of pills to treat people with HIV. These injections are given by health care providers once a month or every other month and require routine office visits.

ART is recommended for everyone who has HIV, and people with HIV should start ART as soon as possible. ART cannot cure HIV, but HIV medicines help people with HIV live long, healthy lives.

A main goal of ART is to reduce a person’s viral load to an undetectable level. An undetectable viral load means that the level of HIV in the blood is too low to be detected by a viral load test. 

People with HIV who maintain an undetectable viral load have effectively no risk of transmitting HIV to a partner without HIV through sex (known as Undetectable = Untransmittable, or U=U). 

Who should get tested for HIV?

The Centers for Disease Control and Prevention (CDC) recommends that everyone aged 13 to 64 years get tested for HIV at least once as part of routine health care. Generally, people who have more risk factors for HIV should get tested each year. Sexually active MSM may benefit from getting tested more often, such as every three to six months.

If you are older than 64 years, your health care provider may recommend HIV testing if you have certain risk factors that increase the chance of HIV transmission, such as:

  • Having vaginal or anal sex with someone who has HIV or whose HIV status you do not know
  • Injecting drugs and sharing needles, syringes, or other drug equipment with others
  • Exchanging sex for money or drugs
  • Having a sexually transmitted infection (STI), such as syphilis
  • Having sex with anyone who has any of the HIV risk factors listed above

Talk to your health care provider about your risk for HIV and how often you should get tested for HIV.

Should pregnant women get tested for HIV?

CDC recommends that all pregnant women get tested for HIV so that they can begin taking HIV medicines as soon as possible if they test positive. Pregnant women with HIV take HIV medicines during pregnancy and childbirth to reduce the chances of perinatal transmission of HIV and any personal health risks. For more information, read the HIVinfo fact sheet on Preventing Perinatal Transmission of HIV.

What are the types of HIV tests?

There are three types of tests used to diagnose HIV infection: antibody tests, antigen/antibody tests, and nucleic acid tests (NATs). Your health care provider can determine the appropriate HIV test for you.

How soon each test can detect HIV infection differs, because each test has a different window period. The window period is the time between when a person may have been exposed to HIV and when a test can accurately detect HIV infection.

  • Antibody tests check for HIV antibodies in blood or oral fluid. Most rapid tests and at-home self-tests are antibody tests. Generally, antibody tests that use blood from a vein can detect HIV sooner than tests done with blood from a finger stick or with oral fluid.
  • Antigen/antibody tests can detect both HIV antibodies and HIV antigens in the blood and are the most commonly used HIV tests. After HIV exposure, antigens will show up in the blood sooner than antibodies.
  • NATs look for HIV in the blood taken from a vein. These tests may also be called viral load tests because they not only detect the virus but also determine the quantity of virus present in the blood. They can usually identify HIV as soon as 10 to 33 days after exposure. NATs are mostly used to monitor HIV treatment and not for routine screening because they are expensive.

A person’s initial HIV test will usually be either an antibody test or an antigen/antibody test. NATs are not routinely used for HIV screening unless the person has had a high-risk exposure or a possible exposure with early symptoms of HIV infection.

When an HIV test is positive, a follow-up test will be conducted for confirmation to rule out inaccurate test results, known as a false positive result. Sometimes people will need to visit a health care provider to take a follow-up test using another blood sample.

Other times, the follow-up test may be performed in a lab using the original blood sample to ensure that the first positive result wasn’t a false positive. Talk to your health care provider who will determine your HIV risk factors and the best type of HIV test for you.

Is HIV testing confidential?

HIV testing can be confidential or anonymous. Confidential testing means that your HIV test results are not available to the public. Instead, your test results are included in your medical record and generally reported to local or state health departments to be counted in statistical reports.

Any personal or identifiable information, such as your name or address, is removed before creating statistical reports or sharing with other health organizations, including the CDC.

Anonymous testing means you do not 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.

Where can someone get tested for HIV?

Your health care provider can give you an HIV test. If you feel apprehensive about talking to your personal physician or family doctor, HIV testing is also available at many hospitals, medical clinics, substance use programs, and community health centers. Use CDC's GetTested treatment locator to find an HIV testing location near you.

Getting tested through a professional health care provider is recommended; however, HIV self-testing kits are available. Rapid self-test and mail-in self-test are the two types of HIV self-tests, but state laws regarding self-testing may limit their availability in some locations.

A rapid self-test is an oral fluid (not the same as saliva) test done entirely at home or in private. The U.S. Food and Drug Administration (FDA) has approved one rapid HIV self-test called the OraQuick In-Home HIV test. More information about the OraQuick In-Home HIV Test is available on the FDA website.

This fact sheet is based on information from the following sources:

From CDC:

From FDA:

From Medicare:

From MedlinePlus:

From the National Library of Medicine:

Also see the HIV Source collection of HIV links and resources.