HIV Testing 101

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Taking an HIV test is the only reliable way to know whether you have HIV.

If you have HIV, it's very important that it's diagnosed. That way you can get the medical care that will keep you in good health.

Whether the result is positive or negative, it'll help you make informed decisions about how to stay safe while having sex -- especially if you know your partner's status, too.

If you are diagnosed with HIV during pregnancy, you can take steps to ensure your baby is born without HIV.

Regular HIV testing is recommended for everyone who is sexually active. For example, if you sometimes have sex without a condom or sex with someone whose HIV status you don't know, the CDC recommends that you get tested every year. Men who have sex with men are recommended to get tested every three to six months.

The CDC also recommends that everyone over the age of 13 should take an HIV test at least once.

It's up to you whether you take an HIV test or not. If a medical provider offers to provide an HIV test or suggests that HIV testing would be a good idea, you can always say that you would prefer not to take a test now.

Where to Take an HIV Test?

You can take an HIV test at a wide variety of health facilities -- in private doctors' offices, pharmacies, community health centers, sexually transmitted disease clinics, free-standing HIV counseling and testing centers, health departments and hospitals.

You could simply ask your doctor or medical provider whether they could give you an HIV test. Also, a nurse or doctor might offer you an HIV test when you are attending a health facility for another purpose. In many clinics, this is routine practice for all patients.

Health organizations can sometimes offer HIV testing outside of medical facilities, at community events or social venues.

The member of staff performing the test should explain the testing process and answer your questions about HIV. He or she might also be able to offer advice on reducing your risk of HIV.

To find testing facilities near you in the United States, visit the CDC's Get Tested website and enter your ZIP code. In addition, your local health department can provide addresses.

If you have private health insurance, Medicaid or Medicare, it will usually cover HIV testing provided in accordance with the recommendations mentioned earlier. There should not be a co-pay.

If you don't have insurance, there are places where you can get an HIV test for free -- check the CDC's Get Tested website.

What Kinds of Tests Are Available?

HIV tests are usually done on a sample of blood, either taken from a vein in your arm or from a small prick on your finger. Alternatively, some tests use fluid from around your gums.

While some types of testing require the sample to be sent away to a laboratory for analysis, rapid tests allow the result to be read within a few minutes.

Most tests detect antibodies to HIV. Antibodies are produced by the body's immune system to fight HIV infection. If you have HIV antibodies, this means you have HIV.

In addition, some tests are able to detect p24 antigen as well as HIV antibodies. These tests are better than antibody-only tests at detecting recent HIV infections.

A home test (OraQuick In-Home HIV test) is available to purchase online or in drug stores. It is a rapid test, using fluid from around your gums, detecting antibodies only.

Many people appreciate the convenience, speed and privacy of home HIV testing. But before testing by yourself, it's worth thinking about how you would cope if the test showed you might have HIV. It would be up to you to seek advice and support. In particular, you would need to go to a medical facility to have the result checked and confirmed.

Do the Different Types of Tests Matter?

Generally, these tests all give accurate results. All diagnostic tests for HIV that are approved by the U.S. Food and Drug Administration (FDA) provide accurate results for the vast majority of people.

For most people, it's probably best to use the test that is most convenient or comfortable for them.

But it's worth knowing that some tests are better able to detect recent HIV infections (those acquired in the past few weeks) than others. If you want to test because you think a recent sexual act or sharing of injection equipment might have exposed you to HIV, it's worth knowing that the most accurate types of testing require a blood sample to be analyzed in a lab. They can detect both HIV antibodies and p24 antigen.

What is the Window Period For HIV Test Results?

These tests will detect the majority of infections acquired more than two weeks ago. Nonetheless, it sometimes takes up to three months for a test to detect a new infection.

For this reason, if you are concerned about a recent sexual act and the first test result is negative, you should have a repeat test three months after the last event that could have exposed you to HIV. A negative result at this stage is almost certainly accurate.

What Does a Negative Test Result Mean?

If your result is "HIV negative," this means that the test did not pick up any sign of HIV infection.

As explained above, tests can occasionally miss infections that were acquired in the past three months -- this is the "window period" of the test. So, if the test result is negative, you can consider that the result accurately tells you that you did not have HIV three months ago.

If you've had unprotected sex since then, it's possible that you could have acquired HIV since. If that's the case, you should have another test three months after the last event that could have exposed you to HIV.

Going forward, regular testing (for example, every six months or year) might be a good idea. You might also want to take to this opportunity to rethink the behaviors that put you at risk for HIV and consider ways that you could reduce your risk.

What Does a Positive Result Mean?

It is very important that a positive test result is checked and confirmed. This is because "false positive" results can occasionally occur due to technical errors. Your blood should be tested again -- a second and maybe third time -- to check that the same result is given.

If your blood sample was sent to a lab for analysis, the lab will have already done this before you are told that the result is HIV positive. You can be confident that this result is accurate.

However, if you tested with a home testing kit or a rapid test (one that gives a result within a few minutes, in your presence), then the initial "reactive" or "positive" result will still need to be verified. You'll need extra tests to confirm the result. You may need to go to a medical facility for follow-up testing; you may only get the result after a few days.

If the confirmed result is "HIV positive," this means you have HIV. Take a deep breath and plan your next steps:

  • See a doctor, even if you don't feel sick. Prompt medical treatment is the best way to ensure that you live a long and healthy life.
  • Work out who you can turn to for emotional and social support. There are organizations out there that can help you.
  • Take steps to avoid passing HIV to others. This may include condoms and HIV treatment.
  • Get advice on disclosing your HIV status to sexual partners. In some states, this is a legal requirement.

There's information and advice on all of these points and more on's Resource Center for the Newly Diagnosed.

How Confidential Are HIV Test Results?

Most often, "confidential HIV testing" is offered. Your partner, family or employer won't be able to find out the result without your permission. As with other medical information, your results are protected by privacy laws.

Nonetheless, the result will go in your medical record and may be shared with health care providers and your insurance company. If the result of your test is that you have HIV, the state and local health departments will be informed. They may contact you, offering help with accessing medical care. They may also offer to contact your previous sexual partners (without disclosing your name) in order to suggest that these individuals take an HIV test, too. You don't have to agree to them doing this.

If you are not comfortable with these conditions, you might prefer "anonymous HIV testing." If an HIV test is taken anonymously, the organization providing the test won't know your name or personal details -- you will be given a unique identifier to receive the test result.

However, anonymous HIV testing is only available in some states and at some testing sites. To find out whether it is available, contact your local health department.

The other way to test anonymously is to use a home testing kit.