It doesn't make sense to compare a study where asymptomatic people were being mass tested for the presence of SARS-CoV-2 RNA with the vaccine trials or the CDC's existing tracking of breakthrough infections, both of which require the presence of symptoms before running any tests. The CDC has even set a lower CT threshold (i.e. higher amount of viral RNA must be present) in order to consider a positive test to be an actual breakthrough infection.

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