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The Latest Guidance from the FDA
Our healthcare system has experienced serious strain since the emergence of COVID-19. At-home rapid testing helps to alleviate some of that strain by giving patients the ability to test themselves from their own homes.
Rapid antigen tests deliver test results in minutes and are known to be a highly effective screening tool in the fight against COVID-19. While the Polymerase Chain Reaction (PCR) lab tests are sometimes viewed as more accurate because of their higher sensitivity levels, PCR tests take upwards of 24 hours to complete and are not an effective method for mass screening.
Rapid tests are federally authorized, readily available, and serve a crucial role in managing the spread of COVID-19.
FDA Recommendations For At-Home Rapid Antigen Testing
Just last week, the Food & Drug Administration announced a new recommendation regarding at-home COVID testing practices.
This announcement was prompted after a new study regarding the performance of screening for COVID-19 using rapid antigen tests concluded that three tests taken with 48 hours between each test provides a higher degree of accuracy than two tests taken over three days.
Previous FDA guidelines for at-home COVID testing recommended repeat testing over the course of 48 hours, usually two tests in this period.
The updated recommendation includes the addition of a third test taken after an additional 48 hours, for a total testing period of about 5 days.
Testing Effectiveness Study
The study conducted by researchers at the University of Massachusetts attracted over 5000 participants, each of whom tested themselves every 48 hours for 15 days using at-home rapid antigen tests.
Results highlighted a significant discrepancy in individuals who were symptomatic versus those who were asymptomatic at the time of the study.
Participants who showed symptoms of COVID-19 and used two rapid antigen tests over the course of 48 hours had a 93% detection accuracy.
However, the group that was not showing symptoms and took two tests over that same 48 hour period, had a detection accuracy of only 63%. When a third rapid antigen test was taken after another two days, accuracy rose to almost 80% percent.
Rapid Antigen Test Reliability
These findings provide conclusive evidence to support the increased COVID-19 detection accuracy of three at-home rapid antigen tests over five days, as opposed to two tests taken over the course of 48 hours.
The study solidifies the fact that rapid antigen at-home testing is effective, both for individuals who are showing symptoms and those that are not, while encouraging the adoption of the three-test routine to ensure maximum accuracy.
Implementation of these new at-home testing recommendations will help to catch more cases before they develop, and alert individuals without symptoms so that they can avoid contact with others.
Apuruv Soni, a lead researcher on the study and assistant professor at University of Massachusetts Chan Medical School said, “this was the type of data needed to instill confidence in antigen testing”.