Get tested for HIV. CDC recommends that everyone between the ages of 13 and 64 get tested for HIV at least once as part of routine health care. People with certain risk factors should get tested at least once a year.

If you were HIV-negative the last time you were tested and answer yes to any of the following questions, you should get an HIV test because these things inc rease your chances of getting HIV.

• Are you a man who has had sex with another man?
• Have you had sex --anal or vaginal-- with a partner who has HIV?
• Have you had more than one sex partner since your last HIV test?
• Have you injected drugs and shared needles, syringes or works (e.g., water, cotton) with others?
• Have you exchanged sex for drugs or money?
• Do you have another sexually transmitted disease (STD)?
• Do you have hepatitis or tuberculosis (TB)?
• Have you had sex with someone who could answer yes to any of these questions or someone whose sexual history you don’t know?

You should be tested at least once a year if you answered yes to any of these questions. Sexually active gay and bisexual men may benefit from more frequent testing (for example, every 3 to 6 months), depending on their risk.

If you think you’ve recently been exposed to HIV during sex (e.g., if the condom breaks or comes off) or through sharing needles, syringes, or other injection equipment (for example, cookers), talk to your health care provider or an emergency room doctor right away about taking post-exposure prophylaxis (PEP). You must start PEP within 72 hours (3 days) of a possible exposure, but the sooner you start PEP, the better.

Also, anyone who has been sexually assaulted should get an HIV test as soon as possible after the assault.

Before having sex for the first time with a new partner, you and your partner should talk about your sexual and drug-use history, tell each other your HIV status, and consider getting tested for HIV and learning the results.

Certain things about your sex partner can put you at increased risk for getting or transmitting HIV. Explore Estimate the HIV Risk to learn more.

Additional Resources:

CDC’s HIV testing basics

Learn about the Centers for Disease Control and Prevention’s HIV prevention campaigns:

Let’s Stop HIV Together: Empowering communities, partners, and health care providers to reduce stigma among all Americans, promote HIV testing, prevent HIV among the hardest-hit populations, and help people with HIV stay healthy.

HIV Treatment Works: Encouraging people with HIV to get in care, stay in care, and live well

Doing It: Motivating all adults to get tested for HIV and know their status

HIV tests are very accurate, but no HIV test can detect HIV immediately after a person gets the virus. Some kinds of tests detect HIV sooner than others. In general, nucleic acid tests (NAT) can detect HIV the soonest, followed by antigen/antibody tests, and then antibody tests.

Most rapid tests and self-tests are antibody tests. Your immune system makes antibodies when you’re exposed to bacteria or viruses like HIV. Antibody tests look for these antibodies in your blood or oral fluid. In general, antibody tests that use blood from a vein can detect HIV slightly sooner after infection than tests done with blood from a finger prick or with oral fluid.

More Information  With a rapid antibody screening test, results are ready in 30 minutes or less.

More Information

A self-test (also known as a home test) is an antibody test you can buy at a pharmacy or online. There is currently one available FDA-approved self-test, the OraQuick In-Home HIV Test.

The OraQuick In-Home HIV Test gives fast results at home. You have to swab your mouth to get an oral fluid sample and use a kit to test it. Results are ready in 20 minutes. If the test says you have HIV, you should go to a health care provider to get follow-up testing. The manufacturer provides confidential counseling and refers you to follow-up testing sites.

Note: Some people have difficulty in conducting an HIV self-test and the test does not perform as it should. If an HIV self-test is invalid as described in the instructions, then the test has not worked. In this case, you will need to use another HIV self-test, or seek testing at a health care provider or testing center.

If any type of antibody test says you have HIV, you will need a follow-up test to make sure you really have HIV. If your first test is a self-test and it says you have HIV, you should go to  a health care provider to get follow-up testing. If your first test is done in a testing lab and it says you have HIV, the lab will do the follow-up testing, usually on the same blood sample as the first test.

More Information After someone gets HIV, it can take about 23 to 90 days for their body to make enough antibodies for an antibody test to detect HIV. This time is called the window period. If you get a negative antibody test result, and you may have been exposed to HIV recently, then you should get another test 3 months after your possible exposure to HIV.

An antigen/antibody test looks for both HIV antibodies and antigens. Most laboratory tests are antigen/antibody tests. Antigens are foreign substances that cause your immune system to activate. The antigen is part of the virus itself and is present during the early stage of HIV infection (called acute infection). If you have HIV, an antigen called p24 is produced even before antibodies develop. A rapid antigen/antibody test is available.

More Information After someone gets HIV, it can take time for their body to make enough antigens and antibodies for an antigen/antibody test to detect HIV. This time is called the window period. The window period varies depending upon the type of antigen/antibody test.  A test performed by a laboratory on blood from a vein can usually detect HIV infection 18 to 45 days after an exposure. Antigen/ antibody tests done with blood from a finger prick can take longer to detect HIV (18 to 90 days after an exposure). When the goal is to tell for sure that a person does not have HIV, an antigen/antibody test performed by a laboratory on blood from a vein is preferred. If you get a negative antibody/antigen test result during the window period, you should get another test 3 months after your possible exposure.

Nucleic acid tests (NAT) look for HIV in the blood. The NAT can give either a positive/negative result or the actual amount of virus present in the blood (known as a  viral load test ). This test is very expensive and not routinely used for screening individuals unless they recently had a high-risk exposure or they had a possible exposure and have early symptoms of HIV infection.

More Information A NAT can detect HIV within 10 to 33 days after a person gets HIV infection. A NAT is usually accurate during the early stages of infection. However, it is best to get an antibody or antigen/antibody test at the same time to help the doctor interpret a negative NAT. In a few people, the amount of virus decreases naturally over time, which can lead to a negative NAT result even though the person has HIV. Taking pre-exposure prophylaxis (PrEP) or post exposure prophylaxis (PEP) may also make a NAT less accurate if you have HIV.

Talk to your health care provider to see what type of HIV test is right for you. They can tell you the window period for the type of test you take. If you’re using a self-test, you can get that information from the materials included in the test’s package.

After you get tested, you need to find out the result of your test so you can talk to your health care provider about treatment options if you have HIV or learn ways to prevent getting HIV if you don’t have the virus.

CDC’s HIV testing basics

Learn about the Centers for Disease Control and Prevention’s HIV prevention campaigns:

Let’s Stop HIV Together: Empowering communities, partners, and health care providers to reduce stigma among all Americans, promote HIV testing, prevent HIV among the hardest-hit populations, and help people with HIV stay healthy.

HIV Treatment Works: Encouraging people with HIV to get in care, stay in care, and live well

Doing It: Motivating all adults to get tested for HIV and know their status

The window period varies from person to person, and also depends on the type of HIV test.  It takes time for the body to make enough antibodies for an HIV test to show that a person has HIV.

In most people, an antibody test can detect HIV 23 to 90 days after infection.  

An antigen/antibody test performed by a laboratory on blood from a vein can usually detect HIV infection 18 to 45 days after an exposure. Antigen/ antibody tests done with blood from a finger prick can take longer to detect HIV (18 to 90 days after an exposure). When the goal is to tell for sure that a person does not have HIV, an antigen/antibody test performed by a laboratory on blood from a vein is preferred.

Most people will have enough HIV in their blood for a NAT to detect HIV 10 to 33 days after infection. This is during the time when someone has acute HIV infection.

Let your health care provider know if you may have been exposed to HIV. Together, you can figure out what type of HIV test you should have.

Ask your health care provider about the window period for the test you’re taking. If you’re using a self-test (also known as a home test), you can get that information from the materials included in the test’s package. If you get an HIV test within 3 months after a potential HIV exposure and the result is negative, get tested again in 3 more months to be sure.

If you think you’ve recently been exposed to HIV during sex (e.g., if the condom breaks or comes off) or through sharing needles, syringes or  other injection equipment (for example, cookers), talk to your health care provider or an emergency room doctor right away about taking post-exposure prophylaxis (PEP) . You must start PEP within 72 hours (3 days) of a possible exposure, but the sooner you start PEP, the better.

Also, anyone who has been sexually assaulted should get an HIV test as soon as possible after the assault.

CDC’s HIV testing basics

Learn about the Centers for Disease Control and Prevention’s HIV prevention campaigns:

Let’s Stop HIV Together: Empowering communities, partners, and health care providers to reduce stigma among all Americans, promote HIV testing, prevent HIV among the hardest-hit populations, and help people with HIV stay healthy.

HIV Treatment Works: Encouraging people with HIV to get in care, stay in care, and live well

Doing It: Motivating all adults to get tested for HIV and know their status