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Dr. Robin’s Covid-19 Updates
How To Use Your Covid Tests
And What They Probably Tell You
Testing, Testing, One-Two-Three Testing
Since so so many people are turning positive let’s talk about testing for another minute.
If Covid has taught all us Junior Pseudo Infectious Doctors anything, it’s that no test is perfect and every test has a failing.
In the olden days the best tests were PCR tests. They can detect the tiniest amount of Covid’s viral material and help identify who is sick.
The “failing” of the PCR tests is that they can be TOO sensitive. Since they can detect even “the tiniest amount of genetic material” they can over-call and give us “false positives” by revealing leftover viral material left behind in the “trash” aftermath of an infection.
Little tiny trashy fragments of Covid aren’t contagious. It takes big whole intact viruses to be contagious.
So just because you have a positive PCR showing some of those trash fragments on Day 15 or 20 or 82 doesn’t mean you are any kind of a threat. A positive late PCR test isn’t a “true” positive indicating contagiousness.
Home antigen tests seem to be much better at showing when you’re infected. They do indeed show evidence…
