Right... lets keep focusing on PCR lab based medical testing for a public health war

A public health test with a:
-24 hour delay is just OK
-48 hour delay really losing its use
-72 hour delay almost irrelevant for transmission
-96 hour delay - waste

cnbc.com/2020/11/18/cov…
2/ We have to recognize that the tools we need to fight this war are sitting right in front of us.

Blocked by a medical enterprise that can't see a forest, just trees

A government that fails to recognize the gravity of the situation we are in

3/ Some people say rapid antigen testing is not good enough. "Some infected people might slip by!"

First: Essentially everyone is "slipping by" right now. People are either tested post-transmissible stage or getting results too late to act.

Most are just not getting tested!
4/ But the biology is perhaps the most important piece. A rapid #COVID19 test is highly sensitive to detect people when they are most infectious. This is no longer in question.

It shouldn't have been months ago. We knew already.
It definitely is not now....
5/ Some people say that the PCR test can detect you a day earlier than an antigen test and so the PCR test is better to find people early before they infect others...

This is faulty thinking. It's the WRONG comparison to make.
6/ The RIGHT comparison is not the sensitivity of the rapid test against the sensitivity of PCR taken at the same time

The correct comparison is: what is the sensitivity of the rapid test at the time the PCR test is resulted....24-96 hours after the PCR swab is collected!
7/ If you take PCR that is 48 hours to return and it detects low RNA early in infxn that the rapid test doesn't detect... Sounds not good for rapid test

BUT 24 hours later the viral load will grown 1,000,000x --> Ag test is Positive!

Yet PCR still not back yet!

...
8/ The POINT is when evaluating sensitivity of a lab PCR against a RAPID test, and worried about rapid test not detecting early infection - we MUST consider the speed/kinetics of the virus - it's why its a RAPID test!

This is why lab-MEDICINE is not same as public health testing
9/ In Lab Medicine we compare two tests against the SAME specimen - b/c it's MEDICINE - and we assume we have "one shot"

In Public Health Testing we consider testing Regimens and Timing/kinetics at a population level. The considerations are VERY different.
10/10 This is why @US_FDA must make a new publichealth test evaluatory pathway that has the flexibility to consider testing situations that are distinct from clinical care.

Mixing them is muddying the expectations for a clinical test and blocking widescale public health tests.
We detail this here....

medrxiv.org/content/10.110…
We also detail this here...

w/ @DanLarremore and Roy Parker
nejm.org/doi/full/10.10…

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More from @michaelmina_lab

21 Nov
(SHORT) Thread
NEW paper on RAPID TESTS

Another terrific study showing rapid tests WORK & can be key tools to combat this virus

Of 897 people w high virus (Ct<25): 888 were detected w Rapid Test

Sens: 99.1%
Spec: 99.5%

medrxiv.org/content/10.110…

*repeat tweet b/c typo in last Image
THINK

If these ppl were screening, this would be 888 INFECTIOUS ppl who'd KNOW they’re contagious–and be empowered to act IMMEDIATELY Instead

In USA today, these 888 INFECTIOUS ppl would simply NOT be tested OR find out ~3-7 days later -> often AFTER contagiousness clears!

2/
In this study there was a specificity of 99.5%!

In other words, out of 1000 tests, 5 people would be called falsely positive

This is OK–simply test again- w another rapid confirmatory test that should come with the first test. Those 5 would NOT be likely to be pos on both

3/
Read 8 tweets
19 Nov
South Dakota

68,671 cases
Pop: 885,000
HIGH test +ve %; i.e. not nearly enough testing

I'd be surprised if catching >1 in 5 cases

If so, does 68,671 => 343,000 cases?

And if so... 39% infected...is SD nearing Herd Immunity?

Should serosurvey much of SD to understand if so.
Note: It's tough to know what the true detection rate is. Is it 1 in 2, 1 in 5, 1 in 8 detected?

We don't know for sure.
Either way... SD has a LOT of it's pop infected.

Since it's one of highest per capita states, will be imprtnt to monitor this state
And no - I am NOT suggesting herd immunity as an option. I'm simply stating the numbers up there and suggesting that we monitor to better understand what has and what will happen.
Read 4 tweets
18 Nov
For anyone wondering what a best-in-class rapid antigen test looks like. This is the @AbbottNews PanBio rapid antigen test.

If you lift up the plastic top (which is cheap) it is a simply paper strip (that white part with the red line)....

1/
These are exceptionally cheap w/ very good accuracy to detect people when they are carrying infectious virus

Extremely easy to use
Simple design

I suggest a model where you reuse the plastic shell (like contact lenses) and just change the paper strip. Simple.

2/
It is really unfortunate though that this particular test is NOT sold in the US. It is sold outside of the United States.

Nevertheless - this is to show that THESE TESTS EXIST.

The US Government should be making them in the 10's of millions daily.

Instead, Americans are dying
Read 4 tweets
18 Nov
HERE IS THE PLAN TO GET US OUT OF THIS #COVID19 WAR

• NO lockdowns
• NO waiting for vaccines
• Reverses cases in weeks

A true public health approach focused on the ppl

To end the public health *WAR* we are in.

RAPID At-Home COVID Testing for All

ti.me/3kEGOoM
This Plan works WITH the people and meets them where they are.

It works WITH all the other public health approaches we are already taking - it does not replace them

It is bold and and ambitious - and addresses the fact that we are actually in a war with a virus...

2/
It is time the government STOPS the nonsence of treating this like scattered medical problems to be addressed medically

We MUST address the pandemic as a public health problem - with the RIGHT TOOLS - only then will the medical issues resolve

Not the other way around

3/
Read 15 tweets
17 Nov
PUBLIC SERVICE ANNOUNCEMENT:

Not All Rapid Antigen Tests Are Equal!

Please do NOT assume metrics same across tests

Some work amazingly well to catch contagious virus. Some not

If you hear a rapid test isn't working well, dont assume its same for all of them

It's not
1/
Rapid antigen tests must catch virus on a paper strip

To catch virus, test manufacturers use ANTIBODIES (yes, antibodies like the ones in your immune system) to catch the virus

They make the antibodies and embed them, in a line, on the paper strip.

Thus a line forms if +ve

2/
Antibodies can come in all shapes and sizes (sort of)

Point is, some antibodies are much more specific and strong binders than others

Some are just... sticky. Some much more directed.

Some grab the virus more tightly - these may be used on the more sensitive rapid tests

3/
Read 6 tweets
16 Nov
VACCINES can work!

Another #COVID19 phase 3 vaccine trial reports awesome results. This time, an estimated 94% efficacy

95 COVID19 detected: only 5! in the vaccine group and 90 in the placebo

But like Pfizer results - need to take w caution... WHY?

1/

investors.modernatx.com/news-releases/…
First, the amazing efficacy from phase 3 at this point for both @moderna_tx and @pfizer vaccines - both mRNA vaccines - is EXCEEDINGLY ENCOURAGING.

These results show that these vaccines are eliciting the correct antibody bases responses to stop symptomatic infection!

2/
What I am worried about is the time scale of the trials thus far:

The leading vaccines are presenting the spike protein to the human immune system. This makes sense! Immunize against spike and stop virus entry into the cells.

3/
Read 13 tweets

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