Q&A on At-Home Rapid Tests
The demand for at-home, rapid COVID-19 tests — sparked by the fast-spreading omicron variant in December — has continued in 2022. With that demand have come questions about the tests’ efficacy, how to use them and where to get them. We answer those queries and more.
We focus on the fully at-home antigen tests, which provide results in about 15 minutes. President Joe Biden has said his administration will provide 1 billion free at-home tests to Americans, beginning Jan. 19.
What is a rapid antigen test?
Antigen tests are viral tests that check for the presence of SARS-CoV-2 viral proteins in a sample from a person’s nose or mouth to help determine if the person is currently infected with the coronavirus.
Some of these require a prescription, but the ones people are most familiar with are the self tests that can be purchased over-the-counter and can be performed entirely at home, with a person taking their own sample, running the test, and reading out the result within 15 to 30 minutes.
Sometimes known as lateral flow tests or lateral flow devices, rapid antigen tests for COVID-19 are similar to pregnancy tests in that they detect proteins in a specimen using antibodies embedded in a test strip. Typically, COVID-19 rapid tests use antibodies that recognize parts of the nucleocapsid, or N, protein of SARS-CoV-2 because more of that protein is made and because it’s less likely to change over time as the virus mutates.
Indeed, in the case of the omicron variant, the majority of the mutations are in the gene that encodes the spike, or S, protein, which is the protein that is used in vaccines to prime the immune system and protect against disease. Compared with previous variants, the omicron variant’s N protein is relatively unaltered, differing by a single short deletion and sometimes, one additional change.
What at-home antigen tests had been authorized by the FDA when Biden took office?
Biden has under his administration,
