Hacker News new | ask | show | jobs
by conistonwater 1617 days ago
Pointless pedantry, just because I've been watching TWiV: the PCR test is detecting virus RNA because coronaviruses have RNA, and there's no DNA there. The rest I absolutely agree with.
3 comments

More pointless pedantry from TViV, as I listen frequently as well: the hosts always point out that RT-PCR tests for the presence of viral RNA, but viral RNA particles being inside your nose or mouth doesn't necessarily mean they are infectious. The scale of CT values is 0–100 and lower CT values means more RNA copies. This is used a proxy for infectivity, though it's not terribly scientific. Furthermore, CT values are rarely (if ever) included on the test results.
More pointless pedantry: PCR only works on DNA, so if you want to test an RNA sample, you’ll need to translate it into DNA first before amplifying it.
You're right, of course! Edited.