The NADAL® COVID-19 Antigen Rapid Test – a chromatographic lateral flow immunoassay – checks for protein fragments from the virus and thus for its direct, physical presence in the body. It is performed using a swab from the oral cavity or the nasopharynx. This is extracted in a buffer solution and then pipetted onto the test cassette. A qualitative result is ready in less than 20 minutes.
The diagnostic sensitivity is 97.56 % (ct value: 20 – 30), and the diagnostic specificity is >99.9 %. That means that positive results from antigen tests are very precise. However, as there is always a residual risk of a false-negative result, when in doubt, a PCR test should be carried out to confirm negative results. The choice between antibody, antigen and PCR tests is not an either/or decision. Rather, the best tactic is a combined application.
