[dabigv13]

The "Stanford antibody test" is the Premier Biotech test (per the Stanford Daily)
This page at Johns Hopkins lists a number of serology tests and their claimed accuracy.  That test has no numbers giiven.

The UK has complained that the tests they were investigating, rated at (Alltest) "Company claims up to 98.6 per cent" and  (Wondfo) no claim published, were not good enough to use. "The problem is after a couple of weeks [after symptoms appear], the detection rate remains at about 50 per cent to 60 per cent, especially in asymptomatic or mildly symptomatic cases."

Some analysis of these tests can be found in [/url][url=https://www.medrxiv.org/content/10.1101/2020.04.09.20056325v1]this unreviewed preprint.

In Austin, one place is advertising non-FDA-approved antibody tests for $45.  These are Aytu Biosciences/Orient Gene Biotech POC tests. "The sensitivity is 87.9% and specificity is 100% for IgG, and for IgM it is 97.2% and 100%, respectively."   However, the manufacturer notes:  "In general, antibodies can be detected 1-3 weeks after infection as there is a window period".

Did a quick read of the paper. Never have I read so many preprint, pre peer reviewed papers, but this is the time of covid. The Wantai total Ab test with 100% specificity looks pretty good. Of concern though is how uniformly poor sensitivity is with the IgG tests, since these are the more mature antibodies.

Could correlate with the other literature showing low levels of IgG in people who had the disease. Doesnt mean they aren't immune necessarily (their bodies could ramp up production when they need it perhaps) but does mean testing for it could be difficult. If only 50-60% sensitivity, that means a lot of people could have had disease but test would say they didn't. The combined tests and IgM tests are more sensitive it seems, but those antibodies are only produced early on. So a complete antibody test may be useful if you had an infection recently, but if you had it months ago, may be an issue.

Good they can get 100% specificity though....false positives probably more dangerous than false negatives all things considered. 

Would love to see data from the Stanford test.

[dabigv13]

The "Stanford antibody test" is the Premier Biotech test (per the Stanford Daily)
This page at Johns Hopkins lists a number of serology tests and their claimed accuracy.  That test has no numbers giiven.

The UK has complained that the tests they were investigating, rated at (Alltest) "Company claims up to 98.6 per cent" and  (Wondfo) no claim published, were not good enough to use. "The problem is after a couple of weeks [after symptoms appear], the detection rate remains at about 50 per cent to 60 per cent, especially in asymptomatic or mildly symptomatic cases."

Some analysis of these tests can be found in [/url][url=https://www.medrxiv.org/content/10.1101/2020.04.09.20056325v1]this unreviewed preprint.

In Austin, one place is advertising non-FDA-approved antibody tests for $45.  These are Aytu Biosciences/Orient Gene Biotech POC tests. "The sensitivity is 87.9% and specificity is 100% for IgG, and for IgM it is 97.2% and 100%, respectively."   However, the manufacturer notes:  "In general, antibodies can be detected 1-3 weeks after infection as there is a window period".

Did a quick read of the paper. Never have I read so many preprint, pre peer reviewed papers, but this is the time of covid. The Wantai total Ab test with 100% specificity looks pretty good. Of concern though is how uniformly poor sensitivity is with the IgG tests, since these are the more mature antibodies.

Could correlate with the other literature showing low levels of IgG in people who had the disease. Doesnt mean they aren't immune necessarily (their bodies could ramp up production when they need it perhaps) but does mean testing for it could be difficult. If only 50-60% sensitivity, that means a lot of people could have had disease but test would say they didn't. The combined tests and IgM tests are more sensitive it seems, but those antibodies are only produced early on. So a complete antibody test may be useful if you had an infection recently, but if you had it months ago, may be an issue.

Good they can get 100% specificity though....false positives probably more dangerous than false negatives all things considered. 

Would love to see data from the Stanford test.