Wednesday, August 19, 2020

More on tests

 Robert Zubrin puts the point well in a National Review essay (thanks to a commenter on my last post). 

There are now a variety of fast coronavirus tests that could be readily administered by businesses and schools and provide results within 20 minutes. These tests require only saliva samples, not deep upper nose swabs, and can be readily administered by practically anyone with very modest training. The FDA just approved “emergency use” of one of them by the NBA. The problem is that they won’t let the rest of us use them. Recently I was offered highly effective and economical rapid tests developed by an extremely well-qualified biotech firm. But FDA rules precluded transporting their tests across state lines. Upon appeal it now appears that the FDA might be willing to authorize such shipments on an “emergency basis,” but only for use in already overbooked clinics certified by yet another bureaucracy.

This won’t do. We need to be able to use the tests ourselves.

No clinics. No prescription. No doctor visit. No faxing forms to insurance companies. 

If we were allowed to use these tests, schools and businesses could test their students and workers at the start of each week and send all virus carriers home by 9 a.m. Monday. We could end the pandemic within four weeks, without needing to shut down any schools or companies. 

Testing every American every two weeks means about 30 million tests a day. 

The authorities can’t possibly administer 30 million tests per day. But we — the people — can do it easily, provided we are allowed to do so. 

We are currently forbidden from doing so. The financial cost is trivial compared to the $5 trillion the government is spending on covid relief.  


  1. Has the federal government spent $5 trillion on COV-19 relief?
    Not according to .

    The sums are as follows according to that federal government website:
    Total budgetary measures (budget appropriation) -- $2.6 trillion, comprising
    Total paid out to-date -- $1.3 trillion;
    Total obligations (commitments that have not yet been paid out) -- $0.2 trillion;
    The amount that has not yet been committed or promised (unallocated) -- $1.1 billion.

    $2.4 trillion short of $5 trillion. The numbers are large, perhaps too large to grasp, but let's not overstate the situation.

    1. You need to take into account foregone tax revenue.

  2. Saliva tests are not that easy. The 20 minute claim in the essay links to the FDA website which links to the approval document found here:

    There it says: "Saliva is first treated with proteinase K followed by a heat inactivation step, and is then directly used as input where the SARS-CoV-2 nucleic acid is reverse transcribed into cDNA followed by PCR amplification and detection using an authorized real-time (RT) PCR instrument."

    With other words: Everyone can collect the sample but analyzing it requires trained personnel, a laboratory, specialized equipment and reagents, and takes at least several hours to complete.

    Not having a nasal swab is the only real improvement when using saliva. The direct analysis without prior RNA extraction has already been described as early as March e. g. by my colleagues:

    The rapid "pregnancy-like" COVID-test is still a pipe dream. And unless there is a real technological breakthrough such a quick test will be antibody based. Coronavirus-specific antibodies, however, do not show up until about a week after infection which means that person likely was infectious for several days before their positive test. Isolating them only after will likely be too late.

    Much easier, less costly than daily testing, and at least as effective would be wearing a facemask, social distancing, frequent handwashing, and self monitoring for symptoms of infections. If everyone would follow those recommendations we already would have reduced infection rates significantly.

    1. Odie: See my August 19, 2020 at 7:55 PM below for a possible technological breakthrough. I do not have the chops to tell you whether it is for real or is just hype.

  3. Carl Heneghan & Tom Jefferson have counterpoints worth considering...

    1. Thanks. I read it. It's about testing for diagnosis in hospital settings, not about tests as improved versions of taking people's temperatures in public settings. Their main complaint is "The harms of false-positive results can be substantial: operations can be delayed or cancelled; patients are kept in hospital, just in case; further testing is required; in some cases, it drives local lockdowns." In a public setting the harm of false positive is that people quarantine needlessly. Well, absent tests a lot of us are doing that!

    2. I would love to read your thoughts on the post by "oldie" at 6:51p

    3. My job is considered essential. I've recently had a team member sent home with Covid symptoms. It turns out those symptoms were not related to Covid; the guy had a bad allergy attack, not unusual in the area we're working. The result is that not just one team, but multiple teams from multiple companies were shut down for a week. This is small potatoes to national economics, sure, but anything times ten to the 9th becomes significant, as my Minerology professor used to say. And it must be remembered that schools are opening, fall seasonal allergy season is here (which means very young children are likely to get ear infections as well), and flu season is coming. We can expect false positives from assessment of symptoms to increase until Thanksgiving at the least.

      The question is not--cannot rationally be--"Does this test give false positives?" The question is "Does this test give false positives at a higher or lower rate than current methods?" If it's lower--even by 10%--this test should be in every school nurse's office in bulk.

  4. Zubrin mentions the NBA sponsored test.

    I posted about it in the Friday Thread Test=vaccine. I am very skeptical about this being usable outside of professionally run labs.

    From the article I linked:

    "The Yale test removes one cumbersome and expensive step -- the extraction of RNA from samples -- that is a core part of nasal swab tests ...

    "(The Yale test) loses a little bit of sensitivity, but what we gain is speed and that it should be up to 10 times cheaper," Grubaugh said. The Yale test replaces the extraction step with the introduction of a reagent -- chemicals mixed with the saliva sample -- and a short heating process that releases the virus genome."

    Sorry, I don't think introducing a "reagent" and heating the sample is the sort of thing that consumers can be expected to do properly at home.

    I am not so doctrinaire a libertarian as to conflate running a modern medical laboratory with ethnic hair braiding as subjects of regulation.

    1. Note: Odie above gives the details on why the Yale/NBA test is not suitable for consumer administration.

  5. I wonder if the Russian vaccine works safely. It has not gone through phase three, the usual process of testing on a larger number of people and then ooking for negative results.

    But what if the negative results are outweighed by the positive results?

    The damage to the economy is not done by the virus but rather by the lockdowns. Thailand has almost no Covid-19 but its economy has suffered just like all Western economies have. So testing will not help recovery unless it is accompanied by no lockdowns and a population that accepts some level of risk to return to normal.

    I wonder if Russia is wrong in this case....

  6. Here is another candidate:

    "In trial, Israeli gargle test gives COVID results in 1 second, at 95% accuracy: Championing it as instant, cheap and reliable, innovators at Israel’s largest hospital say their invention could become the world’s standard COVID screening method"

    By Nathan Jeffay, 17 August 2020,

    Israeli scientists are testing a new ultra-fast gargle-and-spit test for coronavirus on hundreds of patients, and report that so far it is proving 95-percent accurate. The developers have built a USB-powered machine the size of an ashtray, which takes just one second to conduct light analysis of mouthwash that a patient has gargled.

    They are about halfway through a trial of 400 people at Israel’s largest hospital, Sheba Medical Center, and say that if accuracy levels continue to impress, they expect it to become available internationally by the end of the year.

    * * *

    Patients rinse with 10 milliliters of a special mouthwash, and then spit into a tube. The sample is placed in a machine that analyzes it, and reports whether it matches the profile of a sample infected with COVID-19.

    The machine, called the SpectraLIT, does not require any chemicals, and no medical skills are required to operate it. ... the machine shines light through the sample and onto a special chip. “A light source goes thought it, and part of the light is absorbed, and the rest is captured by the sensors,” he said.

    * * *

    The tube and specially-formulated mouthwash that are given to patients will cost 25 cents ... Developers say they are hoping that once the machines are in mass production, they will be available from $200 ...


    At $200, the machine would be highly suitable for lots of settings like ERs, pharmacies, and nursing homes. But, I can't see it being a wide spread home appliance.

    You should also note that the January time frame should see some vaccines.

  7. "We serve 330 million dinners in America every night."

    Hey look. Turns out no Americans are hungry.

    "These tests require only saliva samples, not deep upper nose swabs, and can be readily administered by practically anyone with very modest training."

    Saliva testing isn't accurate, while self-administered RT-PCR nasal swabs only go one inch up the nose (with a cotton swab nearly-identical to a q-tip).

    "The objection that rapid tests can produce up to 20 percent false negatives is irrelevant. Without mass testing we are producing 100 percent false negatives."

    This would be a good point but for it being completely backwards. Bad data is NOT better than no data. Bad data is WORSE than no data.

    "Unfortunately, thus far, all 50 governors have been as deaf as the federal government to the imperative to institute universal rapid coronavirus testing without further delay."

    Maybe - just maybe - 50 independent and widely-disparate governors and the feds are in a highly-unusual agreement because they all see the obvious: rapid tests are junk science.

    1. it isnt bad data. it is a higher error rate. take the test twice. now the error rate is just as good and still far cheaper. you are completely wrong here.

    2. Being partly right (rapid test) is much better than being precisely wrong (no test at all).

    3. The other issue is the false positive rate. What's the specificity on these tests - maybe 95%?

      At 30 million tests per day, that's 1.5 million false positives per day. Covid-19 Projections - which has one of the better performing forecast models - estimates current infections at about 1.3% of the population. So, not only are we getting 1+ million false positives per day, but the number of false positives will be 4x to 5x the number of correctly reported true positives in population-wide screening. (We also have to take into account false negatives in thinking about that ratio.) And that ratio of false positives to true positives only increases as prevalence declines.

      One idea would be to confirm those positives with PCR tests. My understanding is that these tests have very high specificity. The U.S. has been running about 700,000 PCR tests per day, though, so that's a non-starter for capacity reasons.

      So, here's a practical question: how long would it be before a lot of these asymptomatic people with false positives say "screw this" and decide to get on with life rather than quarantine? Some people will understand the math themselves, and it's easy to see word spreading that over 1 million people - per day! - being told to quarantine actually have <25% chance that their positive results are correct.

      Meanwhile, we'd also still have some false negatives circulating in the population. Plus, presumably, some number of asymptomatic people who actually have COVID - the group I think we were trying to find? - because they've heard about the math on false positives.

      Targeted use of these sorts of screening tests, on the other hand, makes some sense to me, because targeted use would practically allow for using PCR tests to verify positives. For example, these rapid screening tests could be a way to screen nursing home workers and residents on a regular basis (i.e., more frequently than they'd be screened if we stick with PCR tests).

      I'm generally pretty libertarian and try to err on the side of less regulation, but I think that releasing these rapid screening tests for use by any and all businesses and schools would quickly turn into an epic fiasco.

  8. If the Israelis have come up with a highly effective test, not allowing FDA approval is appalling. After all! the FDA is employed by the tax payer! In the private sector employees don't tell employers how things work. Push the intransigent FDA or fire them!

  9. The tyranny of the status quo ... .

  10. FDA isn't preventing you from buying tests that are approved. That'd be the corpos who won't sell approved tests to you.

  11. Robert Bosch GmbH has developed a 'rapid molecular test' for the presence SARS-CoV-2 virus:

    A single machine will perform one test every 2.4 hours, according to the promotional information. One hundred machines will perform 1000 tests in every 24-hour period.

    The very rapid tests test for the presence of antibodies. Bosch states in its Q&A section: "What is the difference to other COVID-19 tests, where the test result is available in a few minutes? Ans.--These [very rapid] tests are only able to detect anti-bodies. They are not providing the actual detection of relevant pathogens (viruses). Therefore, the World Health Organization (WHO) does not recommend this type of test."

    An alternative is described here: The test is capable of being performed in the 'field' as well as in a laboratory setting. Results are available within 90 minutes of collecting the sample from the patient. All steps of the three-part test must be performed by a licenced medical technician. The procedure will analyze 16 samples in a 24-hour period.

    Neither product can be used in a home-setting. The through-put rates are 1 per 1.5 hrs, and 1 per 2.4 hours. These rates are consistent with the notion of "rapid". The rate limiting step is one sample per test device at cycle times of 90 minutes and 144 minutes.

    Now, suppose you have a budget for 10 testing stations (devices), and 1,000 students, faculty and staff in your school to test, and you are required to administer a test to each. How long will it take (in terms of a 40-hour work week) to test all 1,000 persons? The device that has a through-put rate of 1 every 90 minutes, conducting 1,000 tests using 10 devices will take 3.75 40-hour weeks; and, the device that has a through-put rate of 1 every 144 minutes, conducting 1,000 tests using 10 of those devices will take six 40-hour weeks. Or, roughly, between one to one-and-a-half months for all 1,000 students, faculty, and staff at your school. Sound feasible? How about a town with a population of 24,000 souls? And, we have yet to consider the constraints imposed by certified medical technician availability and capital budget appropriations.

    To-date, as of yesterday (8/20/2020), 70 million tests have been conducted in the U.S., 21 percent of the population. Seventy million is twice the size of the population of Canada. Say what you will, it is nonetheless impressive in terms of scale and doubling time.

  12. My first inclination here was to jump on the bandwagon of those bashing Cochrane's pie-in-the-sky rapid test vision. But I don't have a better idea, so it feels a bit rude to do so. It's always easier to criticize than create.

    I suspect what's happening here is as follows: (1) there is no methodology of wide-spread testing currently available in the U.S. that's capable of meaningfully slowing the SPREAD of COVID and (2) the Feds/States all know this, so (3) they prefer more accurate tests that help them better TRACK the virus in order to best calibrate reopening cadence (e.g., when to reopen schools, when to increase capacity limits in offices, etc.). Just a guess, but that's sure what it feels like...

  13. I ask everyone proposing more testing a simple question: "What will you do with the test results?" Many have no answer. Those that do have simple solutions such as "Send those that test positive home." That raises another question: "Home to what?". Home to grandma who is tasked with baby sitting while the parents work? Or to a home where the parents must work away from home? In that case, how do you enforce a quarantine on the other members of the home?
    In the case of schools doing the testing, will they rent no longer used isolation booths from the extinct $64,000 question? How do they keep those testing positive from infecting others before the test itself?
    Virtually all those advocating more testing fail to present an entire plan for testing. If they attempted that, it would lead to a lot fewer calls for more testing.

  14. Seriously, why are you not the president John. You would make a way better president than what we have. I do not understand why we are not doing rapid testing and doing a lock down to the infected ones, problem solved.

  15. "The U.S. government has conducted 85 million COVID-19 tests so far with a positivity rate of just over 5%, Girior said. The mean turnaround time is 2.27 days." -- Admiral Brett Giroir, assistant secretary for health at the U.S. Department of Health and Human Services. [Source: ].

    In the same Reuters article: "The U.S. government purchased 150 million rapid antigen tests for COVID-19 from Abbott in a roughly $750 million deal. The portable tests can deliver results within 15 minutes and will sell for $5. They require no additional equipment, and can use a less invasive nasal swab than traditional lab tests." "The U.S. government will send an “overwhelming majority” of the rapid COVID-19 tests it purchased from Abbott Laboratories (ABT.N) last week to governors of states and territories to support school reopenings and other critical tasks,...Other top priorities for the newly purchased tests include day care centers, first responders, and 'critical infrastructure',... .”

    "Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you:" King James version.


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