Two days ago, a document appeared on the FDA website that bears on the question of prior sensitization to SARS-CoV-2 already existing in the population prior to December, 2019. This is an I.F.U. submission from Ortho Diagnostics on their new, SARS-CoV-2 specific serology test. They tested 400 presumed negative samples and got zero cross-reactivity with their antigen. The document does not say this, but I know through other channels that these 400 samples are banked blood samples from prior to the COVID-19 outbreak. You may encounter theories online that the lockdowns have not had any positive effect, and part of that narrative relies on an assertion that the human population has seen this virus before, and already has herd immunity-- and thus we conclude the lockdowns had no effect. This story makes no sense even if herd immunity were a factor in the highly diverse reactions that people have to this virus. But these data show it is simply not true. You can read the entire document here: https://lnkd.in/gY9zmrW
Thanks for sharing. SARS-Cov-2 has three structure proteins, S,M and E. This assay detects anti S protein. Can S protein antibody represent the seroconversion of the patients? What if this S protein for SARS-Cov-2 has low antigenicity? What if the seroconversion relies on other structure peptides too? How do we measure the herd immunity before we understand the immune response for this virus?
True, the herd immunity simply do not the solution, lockdown playing a significant role to contain the infection in any diverse population.
Can this be used as a more reliable test for the virus than the swab?
Uh, science.
This is PCR for RNA response yes? I've heard anecdotally about large false negative clusters for PCR. Obvious questions: when (and under what conditions) were these samples collected and biobanked? What about SARS-CoV-1? Finally, what about the species and mutants we know nothing about yet? I remember the famous study by Chris Mason at Weill Cornell of swabs from NYC metro turnstiles and handles... 70%+ of species (mostly bacteria) were "unknown."
Thanks for sharing! Just more support for #stayhome #staysafe
Partner and Minneapolis Office Leader at Faegre Drinker
4 年So interesting. Thanks for sharing.