Date Issued: Baronial 11, 2022

Woman performing a COVID-19 test on a child

Perform repeat, or series testing following a negative result on any at-abode COVID-xix test, whether or not you accept symptoms.

The U.S. Food and Drug Administration (FDA) is advising people to perform repeat, or serial, testing following a negative result on any calm COVID-19 antigen examination, to reduce the gamble an infection may exist missed (false negative result) and to help forbid people from unknowingly spreading the SARS-CoV-two virus to others. The FDA recommends repeat testing following a negative result whether or non you have COVID-xix symptoms.

At-home COVID-19 antigen tests detect proteins, chosen antigens, from the SARS-CoV-2, the virus that causes COVID-19. At-home COVID-nineteen antigen tests are less probable to observe the SARS-CoV-ii virus than molecular tests, such as polymerase chain reaction (PCR) tests. This is especially true early in an infection or in people who practice not accept COVID-19 symptoms. Currently, all at-habitation COVID-19 antigen tests are FDA-authorized for repeat, or serial use. This means people should use multiple tests over a sure time menstruum, such equally 2-3 days, especially when the people using the tests don't take COVID-19 symptoms. Today, the FDA is highlighting the continued need for repeat, or serial testing when people become a negative result with an at-home COVID-xix antigen test, including recommending additional testing over a longer period of fourth dimension..

Over the grade of the COVID-nineteen pandemic, public wellness scientists have connected to acquire about the SARS-CoV-2 virus and the impact of variants on diagnostic tests that discover SARS-CoV-two. Today'southward recommendations are based on the latest study results from people with likely omicron infection showing that repeat testing subsequently a negative at-dwelling house COVID-19 antigen examination event increases the chance of an accurate result. COVID-xix diagnostic testing remains a cornerstone of our nation'south fight against COVID-19. At-home COVID-nineteen antigen tests, while non perfect, provide a fast and convenient COVID-xix testing pick.

Recommendations:

Before y'all apply a COVID-nineteen antigen exam:

  • Exist aware that at-dwelling COVID-19 antigen tests are less authentic than molecular tests. COVID-19 antigen tests may not detect the SARS-CoV-2 virus early in an infection, pregnant testing shortly after you were exposed to someone with COVID-nineteen could lead to a false-negative issue, especially if you lot don't take symptoms. This is the reason why repeat testing is important.
  • If you plan to use at-home COVID-nineteen antigen tests, have several tests on hand then yous can examination more than one time. You practice not need to utilize the same make of test each time for repeat testing. Visit At-Habitation OTC COVID-xix Diagnostic Tests for a list of all FDA-authorized home tests and for more than data about who tin apply a test and for what ages.
  • Be aware the FDA expects like performance with Point of Intendance (POC) COVID-19 antigen tests performed at a dispensary or doctor'due south role. A negative POC COVID-xix antigen examination result should too exist followed upwards with repeat, or serial testing, and an at-home test could exist used.

When yous use an at-home COVID-19 antigen test:

Follow the exam's step by pace instructions exactly to perform the test and to read the test's results.

After you use an at-home COVID-19 antigen test:

  • If you lot receive a positive result initially or afterwards a repeat test, this means the test detected the SARS-CoV-2 virus and you lot nigh likely have COVID-nineteen.
    • Follow the Centers for Illness Control and Prevention (CDC) guidance for people with COVID-19, including to stay home, isolate from others, and seek follow-upward care with a wellness intendance provider to determine the next steps.
  • If you receive a negative result, the test did not detect the SARS-CoV-two virus at the fourth dimension of that test.
    • If you take COVID-19 symptoms , exam again 48 hours subsequently the start negative test, for a total of at to the lowest degree two tests.
      • If y'all go a negative result on the second test and yous are concerned that you could accept COVID-xix, you may cull to test again 48 hours after the 2nd exam, consider getting a laboratory molecular-based test, or phone call your health care provider.
    • If you do not have COVID-xix symptoms and believe y'all take been exposed to COVID-nineteen, examination again 48 hours afterward the offset negative exam, then 48 hours subsequently the second negative test, for a full of at least three tests.
      • If y'all get a negative result on the second exam, test again 48 hours after the second exam.
      • If yous go a negative upshot on the third test and y'all are concerned that you could have COVID-19, y'all may choose to test over again using an antigen test, consider getting a laboratory molecular-based test, or call your health care provider.
    • If you lot get a positive result on any echo examination with an at-home COVID-19 antigen test, you lot most likely have COVID-nineteen and should follow the CDC guidance for people with COVID-19.

Groundwork

COVID-19 diagnostic tests detect the SARS-CoV-two virus. At-home COVID-19 diagnostic tests are FDA-authorized for self-testing at dwelling, or anywhere. The FDA has authorized both molecular and antigen COVID-19 diagnostic tests for home use.

Overall performance of at-home COVID-19 antigen tests

Nearly at-home COVID-19 tests are antigen tests and do not detect the SARS-CoV-ii virus besides as molecular tests, nigh of which are laboratory-based such as polymerase chain reaction (PCR) tests. Molecular COVID-19 tests are mostly expected to detect the SARS-CoV-ii virus at least 95% of the time when someone is infected. However, at-dwelling COVID-19 antigen tests are generally expected to detect the SARS-CoV-2 virus at least 80% of the time when someone is infected.

When you lot perform an at-home COVID-19 antigen test, and you lot become a positive result, the results are typically accurate. Notwithstanding, if you perform an at-home COVID-19 antigen test, you could get a imitation negative event. This means that the test may not notice the SARS-CoV-two virus that is in your nasal swab sample. This could happen if you examination before long after you go an infection, especially if you don't have COVID-nineteen symptoms. If you receive a faux negative test result, yous may unknowingly spread the SARS-CoV-ii virus to others.

Studies to better empathize at-dwelling COVID-nineteen antigen examination performance

When at-home COVID-19 antigen tests were initially FDA-authorized, the FDA knew that for people to get accurate results, exam instructions would need to include directions for echo, or series, testing. The FDA believed the best style to better understand COVID-xix infections and evaluate test accurateness was to crave test developers to perform follow upward studies with their tests. The studies would need to appraise how well COVID-xix antigen tests could discover the SARS-CoV-ii virus, especially in people without COVID-19 symptoms. Therefore, the FDA required each at-home COVID-19 antigen examination manufacturer to assess how well their test works when used by people with and without COVID-19 symptoms following repeat testing instructions.

In parallel, the FDA collaborated with the National Institutes for Health (NIH) and the University of Massachusetts Chan Medical School and together they designed a comprehensive study to assess at-home COVID-19 antigen test functioning. The study was funded by the NIH's Rapid Dispatch Diagnostics (RADx) Program and included more than 7,000 participants. The results of the study would be bachelor equally a resources to all calm COVID-19 antigen exam manufacturers.

The study participants nerveless their nasal sample and performed an at-dwelling house COVID-nineteen antigen test. Participants who got a negative exam result performed repeat testing every 48 hours, over xiv days. All participants as well collected their nasal sample using a home drove kit and so sent the sample to clinical laboratory for testing with an FDA-authorized molecular test. The study compared the performance of at-dwelling COVID-19 antigen tests to operation of a laboratory-based molecular exam. Results from this report bear witness that repeat testing over a longer timeframe improves test operation and increases the likelihood that an at-home COVID-xix antigen test will notice an infection. These results have farther guided the FDA's thinking that repeat testing after a negative result with an at-habitation COVID-xix antigen test reduces the take a chance of a imitation negative consequence.

FDA Deportment

The FDA is committed to accordingly accurate and reliable at-domicile COVID-19 diagnostic tests for all Americans and will keep the public informed if significant new data about COVID-19 antigen test functioning becomes available.

The FDA is working collaboratively with government and bookish partners to perform studies and brand the results of these studies available.

The FDA encourages at-home COVID-19 antigen test developers with a current Emergency Use Dominance (EUA) to engage with us about how they may be able to use these study results.

Reporting Problems with Your Device

If you think you had a problem with your COVID-19 test, the FDA encourages y'all to report the problem through the MedWatch Voluntary Reporting Form.

Health care personnel employed by facilities that are subject to the FDA's user facility reporting requirements should follow the reporting procedures established by their facilities.

Questions?

If you lot accept questions, email the Division of Industry and Consumer Education (DICE) at Die@FDA.HHS.GOV or phone call 800-638-2041 or 301-796-7100.