Skepticism of High inapparent COVID-19 numbers: Medscape suggests true case fatality rate is at least 0.4%. State governments will be bankrupted by this emergency.

photo by Queven courtesy of pixabay.com

Medscape published a piece on April 19 with critiques of the high estimates issued in a MedRxiv preprint from April 17 that studied 3300 Santa Clara County volunteers.  That research found 50 people with positive tests for antibodies to SARS-COV-2, or 1.5% of those tested.  The conclusion of the preprint was that the case fatality rate (number of people who die after being infected) would be only 0.2% based on the calculations that were done.

If we work backwards and guess that the true case fatality rate is 0.4%, we could slash the final number of inapparent cases by half; this works out to a number of people in the US already infected quite a bit lower.  So perhaps 8 to 10 million people in the US have had infections with COVID-19.  This is considerably less dramatic than the upper limit of estimates given before, but still a lot of asymptomatic or undetected cases.

We will go with the lower numbers because they make more sense.  Nonetheless, we are still left with the desperate need for more testing.  The approach that has been taken has led to a large number of independent antibody testing companies, over 90 already.  The majority of these tests are likely to be inadequate to the task.  Four larger companies have come forward with antibody tests.  Most of them require a formal blood draw rather than finger-pricks and analysis in the laboratory rather than immediate results.  Only time will tell whether these approaches will work.

We need tests with extremely high specificity; the test used in the study cited above had a rate of 99.5%, which sounds good until you do the calculations.  With the prevalence of positive results at the rate given, 1.5%, that specificity works out to half the positive results being false positive.  This is entirely inadequate.

Getting out of this national nightmare requires excellent science and extremely precise testing at a huge scale.  Germany has set the goal of testing everyone in their population, and we should try to do the same.  I fear that the federal government will fail at this task.

By the way (not a minor problem) the state governments and the US Postal Service are being bankrupted by this emergency and state/local services will suffer as a result.  the Postal Service is at risk for being taken over by a private company like Amazon, with the retirement plans of employees wiped out.  Without urgent action by Congress, the result will be a government small enough to drown in a bathtub, just as the libertarians and Republicans wanted.  We should all be afraid, very afraid.