presuming it bears out, this is a key finding.

it shows that many patients that are PCR+ for COV-19 are not shedding infectious virus.

this would imply shorter quarantine needed and provide a testable basis for discharge of isolated patients.

caveat:

specific levels may be assay dependent and centers should establish their own thresholds.

this is a big deal because Ct<34 was achieved in all patients on HCO+AZO by day 12.

explanation:

Tc is measure of how aggressively you need to fluoresce a sample to find virus. if you look hard enough, you can always find something. i could find your DNA in your childhood bedroom with a powerful enough assay

they used that as a comparitor to which samples they were able to culture active virus from and found that above Ct=34 (higher is more sensitive) that virus was detectable via PCR, but not viable to replicate.

this gives us a boundary for contagion that is far lower than many had posited and shortens the window by ~2/3.

it also contradicts all the "viable for 20 days on a surface" theorizing

so, it's less contagious and for much less time than thought

further, we have a test for whether you would be a spreader
that would let us clear people and provide objective basis for hospital discharge etc.