I did a bit of old style medical review.
May 24, 2020
But Is It Useful?
Gary Hurd, Ph.D. | Retired; UC Irvine, Medical College of
Georgia (+ industrial, and private)
Both USC [1] and Stanford [2] have recently released studies
of a commercially promoted method to test for the presence of SARS-CoV-2 IgM
and IgG antibodies in blood. They applied their results to estimates of the
larger population covid-19 prevalence.
These studies must address three questions; it is accurate,
is it representative, and is it useful?
Is It Accurate?
The same rapid antibody test is used in both studies. It is
a variant distributed by Premier Biotech, but made by Hangzhou Biotest Biotech
of China. It was imported and widely distributed under multiple marketing
names, and companies. The US FDA has not approved this method, and the
manufacturer has withdrawn it. [3]
Premier Biotech primarily markets drug testing kits used in
sports, and some industrial/commercial drug testing situations. USC group
received funding from The Foundation for Clean Competition, The Partnership for
Clean Competition [4]. Both are closely associated with Premier Biotech [5].
A preprint provides an additional unrefereed critical review
entitled “Test performance evaluation of SARS-CoV-2 serological assays
[6]"
Is it Representative?
A major objection to the Stanford version of this study was
that they had drawn a sample not representative of the population they claimed
to model. The USC version tried to repair this by using a commercial marketing
firm to generate their sample. However well intended, the sample design was not
followed. The samples in both studies were grossly biased toward upper-middle
class middle-aged white women. These studies failed to be representative and
cannot be generalized.
It is Useful?
A biologically accurate immunological test for our body’s
reaction to SARS-CoV-2 is needed. But reported data from the USC study
questions if the tested method is any better than self reported symptoms.
Specifically two reported facts by USC call this into question.
First, 28.6% of the total sample report prior symptoms. This
returns to the “representative” question.
Second, of the volunteers 72% of total positives had also
reported prior symptoms.
Urging people who experience symptoms to get a direct swab
test will be far cheaper and more effective than the serological test
procedures used here.
REFERENCES
[1] Sood N, Simon P, Ebner P, et al. Seroprevalence of
SARS-CoV-2–Specific Antibodies Among Adults in Los Angeles County, California,
on April 10-11, 2020. JAMA. Published online May 18, 2020.
doi:10.1001/jama.2020.8279
[2] “COVID-19 Antibody Seroprevalence in Santa Clara County,
California”
Eran Bendavid, Bianca Mulaney, Neeraj Sood, Soleil Shah,
Emilia Ling, Rebecca Bromley-Dulfano, Cara Lai, Zoe Weissberg, Rodrigo Saavedra-Walker,
James Tedrow, Dona Tversky, Andrew Bogan, Thomas Kupiec, Daniel Eichner, Ribhav
Gupta, John Ioannidis, Jay Bhattacharya
medRxiv 2020.04.14.20062463; doi:
https://doi.org/10.1101/2020.04.14.20062463
[3] USFDA https://www.fda.gov/medical-devices/emergency-situations-medical-devices/faqs-testing-sars-cov-2#5eca06b54859c
[4] The Partnership for Clean Competition, “… funds 80% of
the worlds anti-doping research and development. Apply for a grant today!”
[5] "With Sports On Hold, A U.S. Anti-Doping
Organization Switches Gears To COVID-19 Research" Karen Price | April 09,
2020 | Team USA. org
https://www.teamusa.org/News/2020/April/09/With-Sports-On-Hold-A-US-Anti-Doping-Organization-Switches-Gears-To-COVID-19-Research
[6] Jeffrey D. Whitman, et al, “Test performance evaluation
of SARS-CoV-2 serological assays” May 17, 2020. medRxiv
https://www.medrxiv.org/content/10.1101/2020.04.25.20074856v2
CONFLICT OF INTEREST: None Reported
