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Fascinating first person recount about getting a positive test but being asymptomatic. Some of it sounds like what I would do. Though she seems much more rational about everything. Also CT numbers? You learn something new everyday.

https://www.npr.org/sections/health-shots/2020/12/18/947407917/i-felt-fine-but-tested-positive-for-the-coronavirus-whats-that-really-mean

 

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23 minutes ago, mission27 said:

Anyone heard from Iowa lately? Are we sure they aren’t just all gone

The sites a use to look at R values suggest Iowa has been under 1 for well over a month so this would make sense lol. I don't take their findings to heart bc both contradict each other but both say Iowa has been doing great. 

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28 minutes ago, BobbyPhil1781 said:

Guess you can always donate blood and get an antibody test lol.

Good stuff!

I'm planning to. Let's me confirm it without specifically getting the PCR test re-done, so if I'm negative I'll know for sure and if I'm positive I'm going to give as much blood as I can anyway.

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52 minutes ago, Xenos said:

Fascinating first person recount about getting a positive test but being asymptomatic. Some of it sounds like what I would do. Though she seems much more rational about everything. Also CT numbers? You learn something new everyday.

https://www.npr.org/sections/health-shots/2020/12/18/947407917/i-felt-fine-but-tested-positive-for-the-coronavirus-whats-that-really-mean

 

The discussion on Ct needs note that the higher the Ct count, by definition the more unreliable the assay.

A PCR test works by exponentially replicating the DNA in the sample each cycle, so that at the end you can start with a sequence of DNA with only a few copies and end up with a billion of them by the 30 or 40th replication. But each time you do a replication, you have to heat the sample to biological temperature, let some biochemistry happen for a while, let it cool, and then repeat. 40 repetitions is a lot of room for enzymes to make potential errors and more importantly for those errors to be exponentially amplified in subsequent cycles.

A validated PCR test for this should have a maximum number of Ct cycles before which the result should be listed as a negative. That's the type of thing you'd find in the SOPs of any analytical lab.

Why this matters is because the article is talking about a difference in the number of cycles to the strength of the case, but neglects to mention a the impact of the positive correlation between the number of cycles and the percentage of false positives that will be incorrectly tabulated as asymptomatic confirmed cases.

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