Thread/
You can categorize testing as follows:
✅Pathogen based (test for presence of virus)
✅Host based (test for patient's response)
✅Molecular/Genetic (RT-PCR)
✅Antigen
✅Viral culture
They target a variety of RNA genes.
✅envelope (env)
✅nucleocapsid (N)
✅spike (S)
✅RNA-dependent RNA polymerase (RdRp)
✅ORF1 genes.
How long can you you have a positive RT-PCR test?
This study reported as long as 8 days after resolution of symptoms.
nature.com/articles/s4159…
No.
What test can determine if we have active (whole) virus?
Nothing commercially available. You have to do this in a lab via cell culture.
wwwnc.cdc.gov/eid/article/26…
nature.com/articles/s4158…
Maybe.
Well...one company was granted an EUA last week. We are told many will soon follow.
But problem is that it may not be sensitive enough. Lots of false negatives according to this.
fda.gov/news-events/pr…
Who's protected? And for how long?
Unknown.
"There is currently no evidence that people who have recovered from COVID-19 and have antibodies are protected from a second infection."
who.int/news-room/comm…
I found it a quite useful summary.
jamanetwork.com/journals/jama/…
End/
NINE.
So is it possible some people may be 'infectious' for a longer period? Probably.
Need more data on infected patients. With serial viral cultures.