Luckily, the issue is a simple one to fix (all things considered).
The tests exist in HUGE numbers across the globe. Just not in the US. The reason? We've asked the FDA to take on an impossible task... to evaluate high quality PUBLIC HEALTH tools, when this is not their job
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The FDA evaluates medical devices - and does not evaluate public health tools
This is THE problem. As long as we consider rapid tests as medical devices (they're not - they're PUBLIC HEALTH transmission detection tools) FDA is forced to fit a square peg in a round hole
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By evaluating as med devices, FDA is forced to ask tests (meant to be specific to contagiousness-a public health issue) to achieve sensitivity to tests that are specific simply to viral RNA, regardless of contagious levels or not. Thus, we've tasked the w an impossible task.
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The simplest solution to increase access to tests in the US (and massively drop costs) is for the president to use executive actions that designate that
-tools used for public health testing, during the public health emergency, are public health tools, not medical devices.
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If this simple change is made, then FDA no longer tasked w evaluating rapid tests (since they don't evaluate public health tools) and can go to CDC/NIH to certify tests as appropriate for public health (i.e high sensitivity for viral loads that are a risk to transmit)
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This allow allow certification of tests "by-right" based on their use in Europe, for instance, opening the US overnight to a massive influx of HIGH QUALITY rapid tests at low cost.
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It will also allow very FAST EVALUTION of rapid tests using appropriate metrics - like sensitivity by viral load, using lab evaluations for preliminary certificatino, cutting time to market from 6-12 month clinical trials (that are not informative) to 2-5 day evaluations
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A very important piece is the temporal relationship between when viral RNA is highest, when antigen tests are highest sensitivity and when people are most likely to be infectious following exposure. While almost no studies directly observe all three together...
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@MarkZlochin@CircusPubes@DrPathHero1 They all fall directly in line with the exact same time period after exposure or - when symptoms are demonstrated, with the same period surrounding onset of symptoms.
So we really do not need empirical data showing transmission and viral load since the kinetics show it all
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@MarkZlochin@CircusPubes@DrPathHero1 A major problem obtaining the direct empirical data is that if someone is testing, they likely aren't infecting others. So, people who are infecting others, you simply are not getting their swab at the same time as they are infecting. So relationships are skewed.
Its common to say ALL kids mask during school, w out mention of daily rapid tests for entry
Yet, it’s heresy to suggest ALL kids test daily and go maskless
- Poor fitting Masks cut transmission, maybe <50%
- Rapid tests cut risk of infectious entering by >90%
I’m NOT suggesting we not do both. But dilemma is:
Why is it that when masks are discussed, rapid tests in AM are not. BUT when rapid tests in AM are discussed, it has to always be followed by “And masks too”.
Demonstrates group think rather than science backed decisions
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We DO need rapid test supply. Many ways to make it happen. Change of how they are designated (as a public health tool) is first step in my view so that we can massively accelerate access and scale
Rapid tests work very well to answer 🧵
AM I INFECTIOUS and a RISK TO OTHERS
This is THE public health ? we care about
I made a BIG chart of rapid tests
- Overall sensitivity vs any PCR pos - what FDA judges
- Sensitivity if infectious (97%!) - what we actually care about
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This data above comes from the UK COVID-19 Lateral Flow Oversight Team.
What the data above shows is that rapid tests are excellent public health tools to quickly identify almost anyone who is currently infectious and needs to isolate
What it also shows is...
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This shows why there is so much damn confusion about if rapid tests are sensitive
Answer: YES they are... if the question is "Am I Infectious Now and do I need to isolate"
However, if we compare them to PCR, then we are asking a different question: Do I have any RNA in me
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- Moderately infectious (ie infect 2 or 3 ppl in a classroom): 90-95%
- Mildly infectious (ie spread to spouse only) ~80-90%
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This Graph of viral load over time helps to explain this sensitivity issue:
Further, symptoms vs no symptoms has no impact on test performance. Studies that say it does are not recognizing the sampling bias that enters their studies.
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While I am tremendously happy to hear the President say this.
I do have my reservations:
Time is of the essence. If we start the scaling process now, it will take a long time.
Meanwhile many many tests exist globally. We could be using those for the time being.
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Importantly, I worry that the 280 million tests that are going to be purchased and produced with the use of the DPA... well, that's less than one test per person over the course of a year. The number sounds big but we do have 330 million ppl in US.
The US is at a critical point & we need greater access to faster tests
Rapid tests are barely available bc they're regulated here as MEDICAL tools-holding them back
Please write an EO that makes COVID testing in US a Public Health good
Thanks
Ppl of the USA
These tests are regulated by FDA as medical devices. Which has greatly limited them!
For pandemic control UNDER AN EUA FOR A PUBLIC HEALTH EMERGENCY, rapid tests should be regulated as critical public health tools, vetted (appropriately) by CDC/NIH.
I had the opportunity to speak to the prior administration about this. Unfortunately it didn't go far despite many ppl trying.
I hope that an administration as forward looking as yours (@POTUS ) would see the benefit of an executive order that stops this deadly silliness.