Becton Dickinson (BD) is touting the results of a small, in-house study of its Veritor Plus antigen test over molecular (PCR) tests to indicate whether an infected person is more likely able to spread SARS-CoV-2.
The peer-reviewed study compared antigen and PCR test results to positive results using a viral cell culture test. Viral growth in the cell culture test indicates the presence of live virus in the patient sample, which may indicate the presence of infectious virus at the time the sample was taken. If no growth is present in the viral cell culture test, it is likely that there wasn’t enough viable virus for the patient to be contagious at the time the sample was taken, according to BD. The study was published in Clinical Infectious Diseases.
Out of 38 positive PCR result specimens tested on the Quidel Lyra SARS-CoV-2 rt-PCR assay, 28 were positive using the cell culture technique. The antigen tests, conducted using the BD Veritor Plus, were positive in 27 of the 28 cell culture positive tests. This data suggests that 10 of the 38 PCR positive results were potentially identifying non-infectious individuals, meaning PCR detected viral RNA fragments or small amounts of intact SARS-CoV-2 virus and that the patient wasn’t actually contagious at the time the sample was taken. However, the BD antigen test agreed with all but one cell culture positive test. Diagnosing and isolating contagious people has been the primary goal for testing during the pandemic, followed by contact tracing and testing.
Reference testing was performed at TriCore Reference Laboratories (New Mexico) and the antigen testing was performed internally at BD (San Diego, Calif.). The study only included specimens from individuals seven days from symptom onset, but investigators said it could be helpful in controlling the spread of the virus.
“This work highlights a key potential value of decentralized point-of-care antigen-based testing and furthers our understanding of the interpretation of antigen test results,” they wrote. “Antigen testing facilitates accurate and rapid detection of individuals harboring infectious virus who may not require direct medical management (due to mild/nonsevere disease), but for whom infection control measures have the potential to interrupt community transmission.”
“Point-of-care antigen tests, as demonstrated in this study with the BD Veritor Plus system, have the potential to significantly change the public health interventions needed to minimize the spread of COVID-19,” said Dr. Charles Cooper, study co-author and BD’s VP of Medical Affairs, in a news release. “By providing a more relevant test to identify individuals that are likely to be shedding infectious virus and therefore transmit SARS-CoV-2, we will be in a better position to contain its spread. Plus, the low cost and scalability of antigen-based testing makes it an important tool to contain and suppress COVID-19 community transmission.”
Quidel did not immediately respond to a request for comment.