Which of the following tests can identify human immunodeficiency virus infection earliest?

Blood tests are the most common way to diagnose HIV. These tests look for antibodies to the virus that the body creates in an attempt to fight the virus.

People exposed to the virus should get tested immediately, although it can take the body anywhere from six weeks to a year to develop antibodies to the virus. Follow-up tests may be needed depending on the initial time of exposure.

Early testing is crucial. If you test positive for the virus, you and your doctor will discuss and develop a treatment plan that can help fight HIV and ward off complications. Early testing also can alert you to avoid high-risk behavior that can spread the virus to others.

Most health care providers offer HIV testing, often with appropriate counseling. Anonymous and free testing also is available. During testing, your doctor will ask about your symptoms, medical history and risk factors, and perform a physical examination.

Content From: HIV.gov•Updated: June 16, 2022•5 min read

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What Can You Expect When You Get an HIV Test?

Your HIV testing experience might be a little different depending on where you get tested.

HIV Testing in a Health Care Setting or Lab

If you take a test in a health care setting or a lab, a health care provider or lab technician will take a sample of your blood or oral fluid. If it’s a rapid test (oral fluid or finger stick), you may be able to wait for the results, but if it’s a laboratory test, it can take several days for your results to be available. Your health care provider or counselor may talk with you about your risk factors, answer any questions you might have, and discuss next steps with you, especially if your rapid test result is positive.

• If the test comes back negative, and you haven’t had an exposure during the window period for the test you took, you can be confident you don’t have HIV.
• If your HIV test result is positive, the lab will conduct follow-up testing, usually on the same sample as the first.

HIV Testing Outside of a Health Care Setting or Lab

If you get an HIV test outside of a health care setting or lab (such as at a community-based organization, mobile testing van, or elsewhere) you will likely receive a rapid HIV test.

• If the test comes back negative, and you haven’t had a possible exposure during the previous 3 months, you can be confident you don’t have HIV.
• If your test result is positive, you should go to a health care provider to get follow-up testing. Counselors providing the test should be able to answer questions and provide referrals for follow-up testing as well. You can use the HIV.gov locator to find a health center near you.

Learn about the different places where you can get an HIV test.

Is HIV Self-Testing an Option?

Yes. HIV self-testing allows people to take an HIV test and find out their result in their own home or other private location. There are two kinds:

• A Rapid Self-Test is done entirely at home or in a private location and can produce results within 20 minutes. You can buy a rapid self-test kit at a pharmacy or onlineExit Disclaimer . The only rapid self-test currently available in the U.S. is an oral fluid testExit Disclaimer.
• A Mail-In Self-Test includes a specimen collection kit that contains supplies to collect dried blood from a fingerstick at home. The sample is then sent to a lab for testing and the results are provided by a health care provider. Mail-in self-tests can be ordered through various online merchant sites. Your health care provider can also order a mail-in self-test for you.

Check to see if your local health department or other organization near you is providing rapid self-tests for a reduced cost or for free. Directly purchased self-tests may not be covered by private health insurance or Medicaid. Be sure to check with your insurance provider and your health care provider about reimbursement for tests that are self-purchased.

Note: State laws regarding self-testing vary and may limit availability. Check with your provider for additional testing options.

Learn more about HIV self-testing and which one might be right for you.

The COVID-19 pandemic has made it more difficult for some people to access traditional places where HIV testing is provided. Self-testing allows people to get tested for HIV while still following social distancing practices. Ask your local health department or HIV service organization if they offer self-testing kits.

How Soon After Exposure to HIV Can an HIV Test Detect If You Are Infected?

No HIV test can detect HIV immediately after infection. If you think you’ve been exposed to HIV, in the last 72 hours, talk to your health care provider about post-exposure prophylaxis (PEP), right away.

The time between when a person gets HIV and when a test can accurately detect it is called the window period. The window period varies from person to person and also depends upon the type of HIV test.

Types of HIV Tests and Their Window Periods

• Nucleic Acid Test (NAT)—A NAT can usually tell you if you have HIV infection 10 to 33 days after exposure
• Antigen/Antibody Test—An antigen/antibody test performed by a laboratory on blood from a vein can usually detect HIV infection 18 to 45 days after exposure. Antigen/antibody tests done with blood from a finger prick take longer to detect HIV (18 to 90 days after an exposure).
• Antibody Test—An antibody test can take 23 to 90 days to detect HIV infection after an exposure. Most rapid tests and self-tests are antibody tests. In general, antibody tests that use blood from a vein detect HIV sooner after infection than tests done with blood from a finger prick or with oral fluid.

Ask your health care provider or test counselor about the window period for the test you’re taking and whether you will need a follow-up test to confirm the results. If you’re using a self-test, you can get that information from the materials included in the test’s package.

If you get an HIV test after a potential HIV exposure and the result is negative, get tested again after the window period. Remember, you can only be sure you are HIV-negative if:

• Your most recent test is after the window period.
• You haven’t had a potential HIV exposure during the window period. If you do have an exposure, then you will need to be retested.

What If You Can’t Pay for Your HIV Test?

As required by the Affordable Care Act, HIV screening is covered by health insurance without a co-pay. If you don’t have health insurance, some testing sites may offer free tests. Use CDC’s Get Tested to search for free testing resources.

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