At what point did the science of rapid tests get lost?? FREQUENCY • ACCESSIBILITY • SPEED are most important aspects of a test for public health Talking about tests not detecting in the 1st 24 hours of contagiousness assumes people are testing in those hours. Most don’t. 1/

Somewhere along the way people though that any test is bulletproof. It’s not. They’ve always been 90% or so sensitive for higher viral load people (>95% if very high viral load) and now w Omicron they may be more like 80% if they are missing day 1. BUT… 5/

There is a bit of a silver lining here in that symptoms are starting earlier than before. Often starting the day after exposure. SO, our bodies are offering us an early warning that sign even w/out a test. Use it! Assume positive. Take the test on day 2 or 3 to confirm. 6/

The show must go on. Nicole Kidman and Javier Bardem are Lucille Ball and Desi Arnaz in #BeingtheRicardos, now streaming on Prime Video.

Important: If I am still positive on a Rapid Test after 10 days, should I still isolate? YES!! MOST people are infectious for less than 10 days, but SOME can remain for longer Assume that if positive on Rapid ANTIGEN, you're still infectious (Not same for rapid molecular/PCR)

Rapid Molecular can stay positive for a bit longer and PCR can stay positive for literally weeks longer. But Rapid Antigen is direct evidence of having quite a lot of virus which can really only persist if virus is currently continuing to replicate efficiently. 2/

Honestly... I'm just not sure how to feel about this at this point. Demoralized. Frustrated. Understanding. Can't reverse time though... so the only thing I can feel now is that, conditioned on where we are, this is a positive move for public health.

This is how we should be thinking of isolation now *2 days of testing negative ends isolation early* (actually I published this argument in April 2020… said 2 days of PCR Ct values above 35 should end isolation - many physicians wanted to crucify me for it)

Cihan Kaya Gayle L. McDowell when a rapid antigen test turns positive, it means there is active replicating virus. When it turns positive quickly and bright, then the amount of virus is very very high still. Yes, should ALWAYS be considered infectious at this stage.

Love this. For people who say rapid tests can't be quantitative and swabs too variable to think of as a quantifiable sample... Here is one great example of just how reliable tests and viral load trajectories can be. This is just cool too.

Rapid tests are exceptionally good at detecting ppl who are infectious and need to isolate - and not weeks after they’ve been infectious Why do we still pretend like PCR is a gold standard when it is absolutely NOT specific to what most people besides doctors care about? 4/

More generally why doesn’t FDA have a regulatory path for anything having to do w Public Health? Has the pandemic not demonstrated how important Public Health tools are? Why try to make them fit in an inappropriate Medical tool Box? Public Health has distinct requirements! 5/

Its finally dawning on me that there is an endless supply of ppl - many in public health & medicine - who will not understand science of testing & how to interpret the sea of (poorly performed) studies (including by CDC) This is a failure of messaging by Federal government 1/

Confusion around rapid tests is becoming immensely harmful at local levels as every small town and city has their own decision makers trying to wade through a mix of confusing and often conflicting messages, with no guidance and no idea who or what to trust. 2/

The frustrating thing is that this doesn’t need to be hard! The science and biology of rapid Ag tests is extremely simple/straightforward if we allow their formal evaluation to be towards why we take the tests: answering “Am I infectious” or “Do I need to isolate still?” 3/

We have a U.S. FDA that STILL will not recognize that people use tests for public health purposes. We ONLY have a regulatory path based on medicine and NOT for public health. Why won’t FDA recognize that tests are used for Public Health in this Public Health emergency ? 4/

THREAD: This is an important study - supports anecdotes and other work by Anne Wyllie Virus growing and detectable in saliva days earlier than the nose! Both PCR & Ag in nose lag saliva 1-3 days In Nose, PCR is 1 day faster than Ag (As Expected) 1/ medrxiv.org/content/10.110…

So proud to know these 4 amazing students!

So much fun working with Robert Singer and Jason Masuda on this project. And more to come!!!

2023 Don Johnson Cup Champions