WHO prequalifies the first two rapid antigen detection tests for COVID-19

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On 17 December 2025, the World Health Organization (WHO) announced the prequalification of two rapid antigen diagnostic tests (Ag-RDT) for SARS-CoV-2, the virus that causes COVID-19. The two tests are the SD Biosensor STANDARD Q COVID-19 Ag Test and the ACON Biotech Flowflex SARS-CoV-2 Antigen Rapid Test (Self-Testing). This marks the first time that rapid antigen tests for SARS-CoV-2 have achieved WHO prequalification.

Rapid antigen-detection tests provide results in 15–30 minutes, are affordable, and can be used outside centralized laboratories – in clinics, community sites and mobile settings – making them critical for timely detection of infectious cases and targeted public-health action. They are a vital complement to molecular (polymerase-chain reaction or PCR) tests, particularly in resource-limited settings with limited laboratory capacity.

Rapid antigen testing remains essential for:

  • detecting and controlling local outbreaks
  • protecting vulnerable populations and health-care workers
  • maintaining preparedness for future respiratory pandemics.
Types of Tests:

Nucleic acid amplification tests (NAATs) are highly sensitive and highly specific tests that detect one or more viral ribonucleic acid (RNA) genes. PCR tests are the most common type of NAAT used for COVID-19 testing. Viral RNA may stay in a person's body for up to 90 days after they test positive. Therefore, NAATs should not be used to test someone who has tested positive in the last 90 days. Most NAATs need to be performed in a laboratory, although some are performed at the point-of-care. Most NAATs produce qualitative (positive/negative) results.

Antigen tests are immunoassays that detect the presence of specific viral proteins, called antigens. A positive test indicates current infection. Antigen tests generally have high specificity, similar to NAATs, but are less sensitive than most NAATs. Because antigen tests have lower sensitivity, FDA recommends that negative antigen tests be repeated up to three times, with each test 48 hours apart to confirm a negative result. Most antigen tests are less expensive than NAATs and can provide results in minutes. Antigen tests are available for at-home testing (self-testing), at the point of care, or in a laboratory.

As noted in the labeling for authorized over-the-counter antigen tests: Negative results should be treated as presumptive (meaning that they are preliminary results). Negative results do not rule out SARS-CoV-2 infection and should not be used as the sole basis for treatment or patient management decisions, including infection control decisions. Please see FDA guidance on the use of at-home COVID-19 antigen tests.

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