Buck-a-day home tests for COVID already exist and would be extremely useful — like “save the world” kind of useful. With truly cheap testing, almost everyone could check themselves every morning before going out to be around other people. Within weeks, most of the infected could know that they are a danger before they are one… and the virus starts to suffocate.
This is how you open the bars, schools, and theatres without a vaccine.
Cheap tests have not gotten much traction yet, because the authorities are mostly fixated on maximizing accuracy and sensitivity. But extremely sensitive tests are really only good for picking up traces of infection in the earlier and later stages of the disease, when it’s much less infectious. When someone is properly infectious, they are pumping out so many viral particles you could probably spot them with a magnifying glass. False negatives could still occur with cheap tests, but mostly only when the signal is weak — not so much virus yet — and therefore also not as important. If the insensitive-but-cheap test doesn’t catch it on Monday, it probably will on Tuesday, because a full blown COVID infection produces truly stupendous numbers of viral particles.
A high-sensitivity test can pick up impressively tiny traces of RNA in a person weeks after infectiousness ended, because viruses leave a lot of RNA garbage lying around, which does not mean a person is still infected/infectious. Quick ‘n’ dirty tests can’t detect that stuff… but they do not need to be useful!
I am cribbing all of this from Laurence J. Kotlikoff and Michael Mina, who wrote about on Jul 3 for the New York Times. See “A Cheap, Simple Way to Control the Coronavirus.”
We need the best means of detecting and containing the virus, not a perfect test that no one can use. That is where paper-strip testing would have the advantage. Their ability to be used more frequently would trump the nasal swab test’s higher sensitivity. Paper-strip testing would also sharply improve diagnosis as those with a positive paper-strip test would still be given a nasal swab test.
Mina was also interviewed on the This Week in Virology podcast on Jul 16, and it was fantastic, specialized but fascinating and highly recommended. It was charming how excited the (virologist) hosts of the show were talking about the interview after it ended — they were bubbling over with enthusiasm. They clearly see it as a game-changer. In the subsequent TWiV episode, Dr. Anthony Fauci agreed wholeheartedly with the strategy — we can’t “let the perfect be the enemy of the good.” And that’s another highly recommended interview, a well-rounded tour of the science of COVID so far.