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A comment on Order your rapid tests from the USPS (US only). Parent comment

Re:Order your rapid tests from the USPS (US only) by fotta on Tuesday January 18, 2022 @01:57PM (#29983976)
If you look at the actual testing data for antigen tests [0], the LoD for them is very high compared with PCR. This means a person needs a high viral load for tests to be effective. For example, the BinaxNOW kits require 140.6 TCID50/mL [1] vs 0.012 TCID50/mL for a PCR test (I picked a random one here) [2]. The FlowFlex tests are even worse, requiring 2500 TCID50/mL [3]. I personally purchased a few of the Lucira tests (not affiliated I promise) because they're more similar to an at-home PCR (they use LAMP) and so the LoD is lower (0.9 TCID50/mL) [4].

[0] https://www.fda.gov/medical-devices/coronavirus-disease-2019...

[1] (pdf) https://www.fda.gov/media/141570/download

[2] (pdf) https://www.fda.gov/media/142193/download

[3] (pdf) https://www.fda.gov/media/152698/download

[4] (pdf) https://www.fda.gov/media/147494/download

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Re:Order your rapid tests from the USPS (US only) by riedel on Tuesday January 18, 2022 @02:22PM (#29984351)
Wow those package leaflets are impressive. We (in Germany) get those Chinese test on an emergency admission and all they have is a single table with specifity and sensitivity (no info on viral load at all). They are however cheap and they still work . The responsible agency is actually testing them recently and at least publish the results: https://www.eurosurveillance.org/content/10.2807/1560-7917.E... . Still they allow companies to sell obviously nonworking tests with nonreproducible test results.
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Re:Order your rapid tests from the USPS (US only) by disabled on Tuesday January 18, 2022 @02:07PM (#29984122)
What unit of measurement is TCID50/ML? Just curious
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Re:Order your rapid tests from the USPS (US only) by fotta on Tuesday January 18, 2022 @02:15PM (#29984230)
I am admittedly not a virology expert but my understanding is TCID50 signifies the concentration at which 50% of the cells are infected when the sample is inoculated with a diluted solution of viral fluid.

Ripped straight from https://www.bio-rad.com/en-us/life-science-research/overlay/...

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Re:Order your rapid tests from the USPS (US only) by dtech on Tuesday January 18, 2022 @02:16PM (#29984255)
The amount of virus necessary to affect half (50%) of the cells in a sample.
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Re:Order your rapid tests from the USPS (US only) by h2hq on Tuesday January 18, 2022 @02:11PM (#29984171)
https://iamanovice.wordpress.com/2011/03/31/tcid50/
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