Let’s get real about coronavirus testing . . .
We do not know how severe the covid-19 epidemic will be or how much economic and social pain it will cause, but it clearly has the potential to kill hundreds of thousands or even millions of Americans, and the economic consequences could include a deep recession and even a financial crisis that will cause misery to tens of millions of people.
Testing is key to getting the epidemic under control, and it is not clear to me that policymakers are being nearly as aggressive about expanding testing capacity as they should be. Think of two alternative testing strategies. One strategy is to selectively test people who have symptoms or who may have been exposed to someone with the disease. The alternative strategy is to develop the ability to do mass screenings for the virus among the general population. (There are various intermediate strategies one can imagine, such as doing mass screenings in local areas with a high incidence of disease.) Of course, selective testing is the place to start, but the ability to do mass screenings would allow us to pro-actively identify and isolate almost all carriers and would thus avoid the need for widespread social isolation which is wreaking havoc on the economy. Selective screenings, in contrast, may or may not be able to contain the epidemic sufficiently to allow normal economic activity to resume.
I am not sure what is being done to expand our testing capacity, but if we want to develop the ability to do mass screenings, we need to make it a priority now. The government will need to contract with equipment manufacturers and other suppliers (of reagents, swabs, protective gear, etc.) for large capacity commitments on a short timeline. I have no idea what this would cost or even if it is feasible, but if there is even a small chance that the epidemic will last for six months or return next winter, it seems that a $10 or $20 billion investment in testing capacity would be short money.
The Democrats should jump on this as they take up the next coronavirus response bill. Not only is it good policy, it will give them an opportunity to highlight the fumbling, timid response of the Trump administration to the crisis.
The first issue was standardization of tests, CDC failed that spectacularly.
When the fed failed, states had to pick up the slack, and the first step was hospital and state labs developing their own tests. Second step was state recognizing results from local hospitals. Third step is semi-automation, the tests we are using are genetic screening tests, so the initial tests are highly manual processes, the material from the swab is mixed with enzymes that chop it into small segments, and they are sorted by weight in a substrate. The dyed and sorted segments leave visible bands that you compare to the reference. This is old tech (just fancy mass spectrometry), we took a field trip to the state DNA lab and performed it ourselves in biology class in high school, I’m in my 40s.
You can automate some of that process and in particular reduce the manual record-keeping. In MA they have passed that next step and also started allowing electronic data exchange with the large commercial labs. That brings your testing capacity up as well, but nowhere near what you need to do mass screening. You’re in the range where for now you can test thousands of people per week and continue to scale up as you add more commercial labs to the system, but without major capital investments you might not be able to keep up with the number of potential cases if they start getting to Italy levels.
We just aren’t at the stage where you can screen for COVID-19 like you can for the flu (put the swab into a liquid in the doctor’s office, give it a gentle shake and wait five minutes to see if it changes color or not).
Also, these lab developed tests are not regulated by the FDA. When you want to get to that simple commercial-scale you need to file and be approved, so you are looking at clinical trials that you can’t get to without the capacity to do commercial manufacturing of your assay already, and if you want someone who isn’t specifically trained administering that test, you need a CLIA waiver.
The investment is high in terms of both money and time.
Up until this point we have had very narrow testing criteria primarily because of the shortage of test and I suppose and arrogance regarding the measures taken to prevent the disease from entering the country.
You had to have recently traveled to a country with an outbreak, showed all the symptoms or been in contact with someone who tested positive.
Now when they report positive cases what are they reporting? They are NOT reporting the number of positive cases in the country right now. What should be reported is the number of tests administered and the fraction that were positive. Then, the only useful information that is being provided by these tests is… The fraction of the population who meets the testing criteria who are positive. This number at any given time should be independent of the number of tests given. The reported number, the number of positive cases is SOLELY a function of the number of tests given and is therefore next to useless. In fact it is destructive because it lead to the idiot in chiefs inclination to limit testing!
Tests need to be pervasive so that they give an accurate picture of the scope of the disease. That means broadening the testing criteria. When the test is in short supply you narrow the testing criteria and then all you are doing reporting on the increasing number of tests.
Hi Eric:
Attached is a graph showing the numbers of tests given per country. As we both know, China and South Korea appears to have gotten ahead of the curve and took the necessary action to flatten the curve. China did it later than South Korea. The US is far behind the rest of the world and I suspect we will pay for it in the end. There is a logarithmic chart in Media showing tests vs. confirmed cases of Covid-19. I am afraid too few countries have done adequate testing to lock on to a true numeric of an increased/increasing ratio. Feel free to use it.
The Chinese have reported there were several pharmaceuticals which appeared to work also and in particular drugs for malaria, Chloroquine and HydoxyChloroquine. One small clinical test in France had positive results recently as reported March 17, 2020. EN24 HydoxyChloroquine
Remdesivir appears to have worked in a limited number of cases also. An issue which we are missing is bacterial infection following viral infection. The Chinese followed up with antibiotics for Strep. The French study uses Azithromycin for treatment of the resulting pneumonia. NYT says it failed and they are sensationalistic in their reporting. The French clinical test had a success rate of 75%. They are calling for a larger load test. Italy presents an opportunity.
I assume you are being hyperbolic.
Testing people who are symptomatic is a perfectly reasonable approach to determine the progression of the disease, including geographic spread assuming that you have a statistically significant number of symptomatic people as a portion of all persons infected.
Can you slow the progression without identifying those who are asymptomatic? Yes, that’s why we are escalating cleaning, distancing, and quarantine actions that are effective against all viruses.
Can you eliminate the disease? Definitely not, but I haven’t heard of anyone claiming they would be able to do that. The goal isn’t to eliminate COVID-19 at this point, it is to restrict spread to permit health systems to operate without getting to an overload point, and cross your fingers and hope that as the infected population increases, we will develop enough community immunity to deal with the disease long term.
SARS had the fortunate characteristic of being most virulent in those who were displaying the most aggressive symptoms. Without that, it would be really hard to completely stop this virus.
JG:
A nice leap to where I did not go – “eliminate.” Some can be carriers and not display symptoms; hence, it is better to test more people.
Until very recently being symptomatic wasn’t enough to rate a test. The criteria stated that you had to have traveled to one of the listed countries recently or been in contact with someone else who had tested positive. This criteria basically assumed no community spread long past the point that this assumption was obviously unwarranted. The criteria was held in place to limit testing because of a scarcity of tests. I agree that we will never have the resources to test asymptomatic people. But we should have enough test to be relaxing the testing criteria rather than tightening them. All healthcare workers should be routinely tested for example.
Can Smart Thermometers Track the Spread of the Coronavirus?
https://www.nytimes.com/2020/03/18/health/coronavirus-fever-thermometers.html
A company that uses internet-connected thermometers to predict the spread of the flu says it is tracking the coronavirus in real time — something that had been impossible, given the lack of testing for the disease.
Kinsa Health has sold or given away more than a million smart thermometers to households in which two million people reside, and thus can record fevers almost as soon as consumers experience them.
For the last few years, Kinsa’s interactive maps have accurately predicted the spread of flu around the United States about two weeks before the Centers for Disease Control and Prevention’s own surveillance tool, the weekly FluView tracker.
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“This is very, very exciting,” said Dr. William Schaffner, a professor of preventive medicine at Vanderbilt University. “This is 21st-century disease surveillance, and we’ve been rooted in the mid-20th century with something very labor intensive.”