Rapid Antigen testing
The Delhi government has commenced COVID-19 testing through the rapid antigen methodology at 169 centres in and around containment zones of the city.
What is ‘Rapid Antigen testing’?
- A rapid antigen detection test (RADT), also known as the rapid streptococcal test, detects the fragments of proteins found on or within the virus by testing samples collected from the nasal cavity using swabs.
- One of the main advantages of an antigen test is the speed of the test, which can provide results in minutes. However, antigen tests may not detect all active infections, as they do not work the same way as a PCR test.
- Antigen tests are very specific for the virus, but are not as sensitive as molecular PCR tests. This means that positive results from antigen tests are highly accurate, but there is a higher chance of false negatives, so negative results do not rule out infection.
- With this in mind, negative results from an antigen test may need to be confirmed with a PCR test prior to making treatment decisions or to prevent the possible spread of the virus due to a false negative.
- Like RT-PCR, the rapid antigen detection test too seeks to detect the virus rather than the antibodies produced by the body.