The Meaning of a Negative HIV Test

In This Article

One would imagine that an HIV test would be fairly cut and dry, with the results either being HIV negative or HIV positive. HIV negative means you have no signs of HIV in your blood; a positive HIV test means that you do have signs of HIV in your blood. You can be positive for HIV even if you don't have symptoms.

Lab technician putting blood sample on a slide for HIV testing
Martin Harvey / Gallo Images / Getty Images

But there is a scenario when a negative HIV test may not be all that it appears. When testing for HIV, there is a short window period when a person can test negative and actually have the virus in his or her system. 

And the reasons are simple: when HIV infection occurs, a person's immune system begins to develop specialized proteins called antibodies, which are specific to the individual pathogen it aims to neutralize (in this case HIV). It is those antibodies that most antibody-based HIV tests detect.

It takes some time for enough of those antibodies to be produced for an HIV test to detect them. Therefore, if too little HIV antibody has been produced when a person gets tested, the test result will be returned as negative despite the fact that an actual infection has occurred.

Negative HIV Test Accuracy

Some types of HIV tests will only look for antibodies. HIV testing done in a doctor's office may also be able to detect HIV proteins (i.e.antigens) produced by the virus, which can be detected sooner after exposure, shortening the window of detection.

Most physicians will recommend repeat testing three months after exposure to ensure one has a truly negative HIV test result. Some doctors will also recommend another HIV test six months after.

Newer testing assays, employing combination antibody/antigen detection, are far more accurate and sensitive than older generation antibody tests. These are more capable of detecting HIV during the early, acute stages of infection, shortening the window period by as much as a month.

These tests work by detecting the HIV-specific proteins called antigens, which initiate the immune response and are therefore produced more rapidly after infection than antibodies.

If all of the tests are negative, and a person has had no new HIV exposures, then they are considered to be HIV negative and clear of infection.

However, if a person has another possible exposure to the virus between tests (such as condomless sex or shared injected drug use), the tests will need to be repeated, starting over from the point of the new exposure.

Always speak with your health care provider about when you need to be tested and if retesting may be needed to provide greater confidence in the results.

Testing Caveats

Please note that while many of the newer HIV tests—like RNA-based tests or aforementioned antibody/antigen tests—may have a shorter window period, their accuracy and sensitivity can vary, sometimes considerably.

Even among the combination assays, some are known to be 87% accurate during acute infection while others top out at 54%.

With all this being said, rapid HIV tests are still commonly used in clinics and at home, and they test for HIV antibodies. In 2012, the Food and Drug Administration (FDA) approved the first rapid home-use HIV kit, OraQuick. Available in most retail drug stores, OraQuick detects HIV antibodies in saliva with results in 20 to 40 minutes.

But unlike similar tests are given at clinics and hospital, the in-home version will produce approximately one false negative result out of every 12 tests performed. If the test is performed incorrectly or too soon, the likelihood of a false result will only be greater.

If using an in-home test, don't take any chances. Contact the 24-hour helpline listed on the package insert if there are any questions, doubts, or concerns about the accuracy and use of the device.

What If You Are Exposed to HIV?

 If you think you have been exposed to HIV, go immediately to a doctor or an emergency room and get tested right away. You can receive post-exposure prophylaxis, an HIV medication that may decrease your risk of developing HIV, ideally if started within 72 hours of exposure.

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  1. HIV.gov. Understanding HIV test results. Updated May 14, 2018.

  2. Michigan Medicine, University of Michigan. Human immunodeficiency virus (HIV) test. Updated July 20, 2018.

  3. Centers for Disease Control & Prevention. HIV testing. Updated November 8, 2019.

  4. Avert. How do HIV tests work and what's involved? Updated November 12, 2019.

  5. Pilcher CD, Louie B, Facente S, et al. Performance of rapid point-of-care and laboratory tests for acute and established HIV infection in San Francisco. PLoS ONE. 2013;8(12):e80629. doi:10.1371/journal.pone.0080629

  6. Food & Drug Administration. First rapid home-use HIV kit approved for self-testing. Updated September 8, 2014.

  7. Centers for Disease Control & Prevention. PEP. Updated August 6, 2018.