
Daily coronavirus testing at home? Many experts are skeptical - bookofjoe
https://www.nytimes.com/2020/09/06/health/coronavirus-rapid-test.html
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benzible
I'm glad to see mention in this article of the #1 issue with antigen test such
as Abbott BinaxNOW (the one the fed. govt. just bought 150M of): 98.5%
specificity = 1.5% false positives. Test a school of 1200 with an actual 0%
prevalence and you'll get about 20 false positives. This will look like an
outbreak, and cause chaos.

Anyone responsible for server infrastructure knows what happens when you get a
bunch of false alerts from your monitoring service - you send those emails to
your spam filter [i.e. assume every positive is false] or turn off monitoring
altogether [i.e. stop testing]. Think about 20X false positives per day. Also
if people are self-testing, they'll assume their test is a false positive and
just won't report the results.

Confirmatory lab testing could avoid a full 10-day quarantine but the time to
get an RT-PCR test and then get the result (24-72 hours when the system isn't
overloaded) means several days of disruption for those 20 kids (/ faculty /
staff).

I think this essentially kills this concept, assuming other antigen tests have
similar specificity. The Quidel antigen test has had a couple of high-profile
false positive incidents already, so I suspect that is the case.

