BD (Becton, Dickinson and Company) (NYSE: BDX), a leading global medical technology company, today announced the publication of a peer-reviewed study that shows BD's antigen test may be more selective than PCR (polymerase chain reaction) molecular tests at detecting people who are contagious and able to spread COVID-19 disease.
Because as has been stated here the PCR test isn't remotely the gold standard of accurate diagnosis. Despite the spin.
The 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.
Out of 38 positive PCR result specimens tested, only 28 were positive using the cell culture technique. The antigen tests, conducted using the BD Veritor™ Plus System, 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, (that's a more then 25% error margin in this study alone- but we are all well aware that the real number is higher depending on CT's) 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.
"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."
The new clinical data was published Jan. 22, 2021 in Clinical Infectious Diseases, an official journal of the Infectious Diseases Society of America.