Michael Mina explains this means “ALL tests will falter on day 1” (not that rapid antigen tests are uniquely bad), but I imagine that doesn’t change the fact that rapid tests are less accurate for Omicron?). He notes that UK Gov found no impact on sensitivity for Omicron, but it seems like a lot of tests in the UK recommend throat swabbing, and that could impact accuracy for Omicron for tests like BinaxNOW which are nasal only)
My best guess: for detecting people who are infectious but asymptomatic, antigen tests will likely perform approximately as well with Omicron as they have with Delta. Because Omicron infections ramp up so fast, however, I’m reducing my guess for how long you can trust the results from 12 hours to 6 hours. (That is to say, if you tested negative this morning, you shouldn’t assume that you aren’t infectious this evening).
In addition to the data you cite, Abbott claims their testing shows no decrease in BinaxNOW effectiveness against Omicron. That would also be my prior. I’m curious what the FDA has found, although they’ve been coy about releasing details. I assume we’ll see more data soon.
Any thoughts on how to adjust this for recent findings that omicron is more susceptible to testing negative in the early stages of infectiousness?
The findings:
Preliminary results from the NIH: https://www.politico.com/news/2021/12/28/fda-antigen-tests-reduced-sensitivity-omicron-526217?fbclid=IwAR22ulLUhteXrFdhFiuYMLa35Ha1BXFNT_z4QlA6f6ql3nSO8tQ2Q7_WfoU
Michael Mina explains this means “ALL tests will falter on day 1” (not that rapid antigen tests are uniquely bad), but I imagine that doesn’t change the fact that rapid tests are less accurate for Omicron?). He notes that UK Gov found no impact on sensitivity for Omicron, but it seems like a lot of tests in the UK recommend throat swabbing, and that could impact accuracy for Omicron for tests like BinaxNOW which are nasal only)
This: https://www.businessinsider.com/how-to-trust-rapid-covid-test-result-2021-12?amp&fbclid=IwAR3pio-S_xkw4uUOL07sy1lYTapjOBGzRm1iHg0Pe0GFL5aJ1NUXpYfmCGs
Excellent question!
My best guess: for detecting people who are infectious but asymptomatic, antigen tests will likely perform approximately as well with Omicron as they have with Delta. Because Omicron infections ramp up so fast, however, I’m reducing my guess for how long you can trust the results from 12 hours to 6 hours. (That is to say, if you tested negative this morning, you shouldn’t assume that you aren’t infectious this evening).
In addition to the data you cite, Abbott claims their testing shows no decrease in BinaxNOW effectiveness against Omicron. That would also be my prior. I’m curious what the FDA has found, although they’ve been coy about releasing details. I assume we’ll see more data soon.