Philip J. Peters, MD
May 20, 2013
On July 3, 2012, the US Food and Drug Administration approved the OraQuick® In-Home HIV Test, a rapid home-use HIV test kit that can be purchased over the counter and online. The kit provides a test result in 20-40 minutes and allows patients to conduct a self-test in their own home. The kit, which tests a sample of fluid from the mouth, is approved for sale in stores and online to anyone age 17 years and older.
Given the availability of a home-use HIV test, should primary care clinicians advise their patients to use this test, and in what situations is it expected to be most useful?
The Centers for Disease Control and Prevention (CDC) recommends HIV screening for all persons aged 13-64 years, regardless of risk, in healthcare settings where the prevalence of undiagnosed HIV is ≥ 0.1% or the yield of screening is at least 1 new HIV infection identified per 1000 persons screened.[1]
Annual HIV testing is recommended for those at high risk for HIV infection. The best approach for patients is to go to a physician and get tested as part of regular medical care, which is what the CDC recommends. Home-use self-testing is not a substitute for getting tested by a healthcare provider. Primary care clinicians should continue to encourage their patients to get tested for HIV.
Some patients might be reluctant or reticent to test for HIV with their provider or prefer the convenience of HIV testing at home.[2] Having access to a home-use, over-the-counter HIV test could lead to increased HIV testing and earlier HIV diagnoses among people who are not currently getting tested for HIV. If so, it will be an important advance.
Some patients at high risk for HIV infection may benefit from frequent (every 3-6 months) HIV testing. For these patients, home-use self-testing might be convenient.
How should physicians counsel patients who use the home-use HIV test?
It is important for patients to read and follow the test instructions carefully. Performing the test incorrectly can result in an invalid (uninterpretable) test result. In a clinical study, 1% of people who took the test did not get an interpretable test result.[3] A 24/7 support center toll-free number is provided with the test instructions in case there are any questions about how to perform the test correctly. Patients should be aware that in a clinical study, the home-use HIV test did not detect every HIV infection. Among people determined to have HIV infection, approximately 1 in 12 had a negative home-use HIV test result (8% rate of false negative results),[3] so patients should be counseled that a negative home-use HIV test result does not completely rule out HIV infection. Compared with a blood test performed by a healthcare provider, there is a trade-off for the convenience of self-testing oral fluid at home.
Patients should also be aware that this test does not detect recent HIV infection. This test detects antibodies against HIV approximately 3 months after infection occurred. Patients who are concerned about very recent HIV exposure should discuss this with their healthcare provider to determine whether medication to prevent HIV infection (eg, antiretroviral postexposure prophylaxis for HIV exposures within 72 hours) or diagnostic tests for early HIV infection (eg, a fourth-generation combination HIV antigen/antibody test or an HIV RNA test) are indicated.
Is additional HIV testing recommended for patients who report a positive home-use HIV test result?
Like any rapid test, a positive or reactive home-use, over-the-counter HIV test is a preliminary positive result that needs to be confirmed with additional testing. HIV testing always involves at least 2 tests. Patients who report a positive home-use HIV test should be counseled that they have a preliminary positive test result and must have blood drawn and sent to a laboratory for HIV testing to determine whether HIV infection is truly present or whether the test result is a false positive. (In clinical studies, only 1 false positive result occurred in 4903 tests on HIV-negative people.[3]) Patients with a confirmed positive HIV test result should be immediately referred for HIV medical care.
Given the high rate of false negative results, when should a clinician consider retesting a patient who reports a negative home-use HIV test result?
Self-testing for HIV at home is not intended as a substitute for going to a healthcare provider and getting tested. Patients who are concerned that they might have been exposed to HIV should be offered an HIV test even if they report a negative home-use test result. The clinical trials showed that the home-use HIV test was positive in 92% of persons who were infected. This is not as accurate as a blood test performed by a healthcare provider. Also, the home-use HIV test does not detect recent HIV infection (less than 3 months after exposure). Some laboratory tests (fourth-generation combination antigen/antibody tests or HIV RNA tests) can detect HIV as soon as 10-14 days after infection. Patients who might have been exposed to HIV very recently (that is, within 72 hours) also should be evaluated for possible use of postexposure prophylaxis with antiretroviral drugs. In addition, patients with ongoing potential exposures to HIV infection should be retested at least annually. Some patients, such as sexually active men who have sex with men, might benefit from testing as often as every 3-6 months. Therefore, the decision to repeat HIV testing should be based on the patient's specific circumstances.
How should clinicians advise partners of high-risk individuals about taking the home-use HIV test?
Partners of people at high risk for HIV infection are an important group to test for HIV infection. Clinicians with patients at high risk for HIV infection should encourage them to discuss HIV testing with their partners and urge their partners to be tested for HIV infection as well. Ideally, these partners could come to your office and receive HIV testing as part of their medical care. Further information on finding an HIV testing site is also available online. Some partners, however, may be reluctant or reticent to test for HIV because of perceived stigma or other reasons. In addition, some couples may prefer to test together, and HIV testing at home offers a convenient way to do that. Patients should be reminded that self-testing for HIV at home does not detect recent HIV infection (less than 3 months after exposure). Because individuals with recent HIV infection are at especially high risk for transmitting HIV infection to their partners, a negative home-use HIV test should not be used to make decisions about behaviors, such as having unprotected sex, that might place them at risk for HIV.
Web Resources
For information on CDC's HIV screening recommendations in healthcare settings: http://www.cdc.gov/actagainstaids/hssc/index.html
For general information on HIV testing: http://www.hivtest.org/
For general information on HIV infection: http://www.cdc.gov/hiv/default.htm
Philip J. Peters, MD, DTM&H, is a Medical Officer with the Division of HIV/AIDS Prevention, US Centers for Disease Control and Prevention, in Atlanta, Georgia. Dr. Peters is the activity leader for HIV testing in the Division of HIV/AIDS Prevention's Epidemiology Branch. He is responsible for conducting epidemiologic and biomedical research activities to evaluate acute HIV infection and important HIV-related coinfections such as Staphylococcus aureus, influenza, and hepatitis B virus. Dr. Peters received his medical degree from Cornell University Medical College. He completed his clinical training in internal medicine at Massachusetts General Hospital and his clinical training in infectious diseases at Emory University. He began his career at the CDC in 2006 when he joined as an Epidemic Intelligence Service Officer. His professional interests include improving HIV diagnosis in the clinical setting.
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