4 ms·

> because 80% of people exposed to covid don't produce antibodies Are there any data available to support this claim? That would mean that the virus is cleared

> because 80% of people exposed to covid don't produce antibodies Are there any data available to support this claim? That would mean that the virus is cleared by the innate immune system and not the adaptive, but it is still a pretty bold statement. The last I read (a Nature Genetics study, if I recall) was that the antibody quantity was lower in milder cases (but with a large inter-person variability).

gizmo 6y ago
Yes, I linked to a relevant paper in this thread. (And I think it's what you would expect for a disease that is non-symptomatic for many young/healthy people.) > That would mean that the virus is cleared by the innate immune system and not the adaptive Not necessarily, because adaptive antibodies produced through previous exposure to coronaviruses can also bind to covid19.
- lbeltrame 6y ago
  At least the abstract says something different: > Nevertheless, rare but recurring RBD-specific antibodies with potent antiviral activity were found in all individuals tested, suggesting that a vaccine designed to elicit such antibodies could be broadly effective. Very low levels, but still produced. (Note that I still have to dig through the paper.)
  - gizmo 6y ago
    My understanding is that those RBD-specific antibodies are not necessarily produced as a response to covid19, but I could be mistaken. In addition: > Plasmas collected an average of 39 days after the onset of symptoms had variable half-maximal neutralizing titers ranging from undetectable in 33% to below 1:1000 in 79% Of course this is only a single study and more research is needed, but I notice people draw way too strong conclusions from studies that show low seropositivity prevalence.
    - lbeltrame 6y ago
      It looks like another preprint found antibodies in the airways mucosa instead of blood. That would perhaps explain why some were undetectable.

gizmo 6y ago

Yes, I linked to a relevant paper in this thread. (And I think it's what you would expect for a disease that is non-symptomatic for many young/healthy people.) > That would mean that the virus is cleared by the innate immune system and not the adaptive Not necessarily, because adaptive antibodies produced through previous exposure to coronaviruses can also bind to covid19.

lbeltrame 6y ago
At least the abstract says something different: > Nevertheless, rare but recurring RBD-specific antibodies with potent antiviral activity were found in all individuals tested, suggesting that a vaccine designed to elicit such antibodies could be broadly effective. Very low levels, but still produced. (Note that I still have to dig through the paper.)
- gizmo 6y ago
  My understanding is that those RBD-specific antibodies are not necessarily produced as a response to covid19, but I could be mistaken. In addition: > Plasmas collected an average of 39 days after the onset of symptoms had variable half-maximal neutralizing titers ranging from undetectable in 33% to below 1:1000 in 79% Of course this is only a single study and more research is needed, but I notice people draw way too strong conclusions from studies that show low seropositivity prevalence.
  - lbeltrame 6y ago
    It looks like another preprint found antibodies in the airways mucosa instead of blood. That would perhaps explain why some were undetectable.