Rapid Antigen Tests are used under certain circumstances using self-collected swabs from the anterior nose. RATs provide an alternative to PCR tests, the nasopharyngeal swabs collected by health professionals.
While the results of RATs are not as reliable as PCR tests, the speed and simplicity make using RATs an important complementary tool which can assist efforts to curb the current pandemic and reduce risks in certain day-to-day situations.
Rapid Antigen Tests can deliver results within 20 minutes, compared to 2-5 days with PCR tests.
Research at the Charité’s Ambulatory Coronavirus Testing Facility compared the success of RATs with PCR results.
Individuals with COVID symptoms were tested using self-collected nasal swabs using the Rapid Antigen Tests. The medical staff also conducted rapid antigen and PCR tests on the individuals.
39 out of a total of 289 participants (13.5 percent) were diagnosed with COVID-19, based on PCR results. In 31 of these infected individuals (nearly 80%), the professional-collected nasopharyngeal swabs also produced a positive result with the rapid antigen test. For self-collected swabs collected from the anterior nose, correct results were obtained in 29 (approximately 74 percent) of the infected individuals.
“We had of course expected rapid antigen tests to be less sensitive than PCR,” says PD Dr. Denkinger. “Upon closer inspection, however, cases of antigen tests missing infections were primarily associated with patients who had low viral loads.”
When looking exclusively at patients with high viral loads, the researchers found that the antigen tests correctly identified every single positive sample obtained via nasopharyngeal swab, and nearly 96 percent of self-collected swabs.
What do you if your RAT test is positive?
If you get a negative test result and do not have symptoms, you can continue with your day to day routines and return to work.
If you get a positive test result, you must self-isolate immediately and get a PCR test. You will need to get a follow-up PCR test immediately from your doctor or community testing centre. It is also important to report your RAT result with the official My Covid Record.
If a result is failed or indeterminate you must take the test again.