An ideal screening test is one with high sensitivity.
During a pandemic of a fast moving virus that transmits asymptomatically, it is difficult to detect people before they transmit to others.
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This far we have focused almost all of our screening efforts on the use of the very sensitive (and specific - a good thing) qPCR.
The qPCR meets the molecular needs of detecting this virus. It has an extraordinary sensitivity.
But it is extremely limited
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Focusing on PCR as a screening method today necessarily equates to low frequency screening.
With a virus that transmits before people feels symptoms, low frequency testing equates to missing the infectious stage of most people’s infections. Catching them too late, or never.
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So in the @NEJM piece, we suggest that the goal should shift away from the sensitivity of the test to detect molecules and towards the sensitivity of the testing program to find infectious people and filter them out before infecting others.
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In other words, we want to focus on the *sensitivity of the testing regime* to detect and stop transmission, rather than focus on the analytical sensitivity of the test to find molecules in the relatively small number of samples that can be reasonably tested.
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The PCR test is wonderful and has a terrific sensitivity. But it comes at the expense of being very limited.
In short, the best test in the world with the highest molecular sensitivity has a near zero % sensitivity to detect infectious people if it can barely be used.
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If the world can create cheaper faster tests that can be produced and distributed to millions of people and used frequently, then the greater frequency more than makes up for the potentially lower molecular sensitivity of the frequent and accessible tests.
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Ultimately this means that a low molecular sensitivity test that is used very frequently by many people will have a MUCH greater *sensitivity to catch infectious people* before they have a chance to spread virus to others.
To put this in perspective...
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Collectively, in US, our screening programs based on high molecular sensitivity PCR likely catch less than <5% of infectious people in time to act and prevent them from spreading.
Thus, our PCR based testing has a <5% sensitivity to detect #COVID19 before it spreads.
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This is why we must rethink the meaning of sensitivity of #COVID19 tests. We must move away from thinking just about the ability to detect molecules and towards the ability to detect infectious people.
The sensitivity of the testing program must be high - not the test.
Joseph Hibbeln MD has long researched and advocated for optimizing nutrition, including studying things like seafood consumption in pregnancy and role of mercury consumption and whether it is linked to autism. Generally he’s come out saying it’s not.
Summary: No evidence of anti science or anti vaccine. Likely very balanced and nuanced rigorous scientist to serve on ACIP.
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Cody Meissner MD
Is a pediatric infectious disease expert at my Alma mater - Dartmouth. He is a rigorous scientist and has defended vaccines while formally recognizing underlying issues that are causing people to turn away from them - such as vaccine success driving down disease - affording people the luxury of focusing on very rare side effects while forgetting the real impacts of the diseases.
One of the most common tropes is that measles is fine & doesn’t cause damage…
This is highly inaccurate
Measles literally grows by infecting and killing memory immune cells. It causes loss to existing immunity creating vulnerabilities & acute damage that is often severe
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To discover the massive-stealth-impact measles has on immune protection against infections not associated w measles, we looked at what happened in populations after measles outbreaks swept through, decade after decade across nations…