Test, test, test.
That has become the mantra in battling the novel coronavirus.
The more testing we do, the more information we have, and the better decisions we can make about the best way to move forward.
This is a sensible strategy, but only testing the sickest among us is giving us incomplete information, and wasting valuable time.
What we really need to understand is how prevalent the virus is in the overall population, both in terms of the current active cases and those who have already had it and recovered.
We know from Iceland (the only country thus far doing randomized testing of the broad population, including those without symptoms) that both groups are likely to be much larger than the reported case numbers, but how many multiples larger remains unknown. The only way to resolve that is with testing a broad sample that is representative of the population at large.
How can we do that?
Start with picking any town in New York (the state most impacted by the virus with the information we know today) that is representative of America in terms of health and age distribution, and test every single person. There are many towns in the suburbs of Long Island and Westchester with a population of 5,000 to 25,000 that would qualify, where we could go door to door (or setup a drive-up site) and test every single resident in a matter of days.
Two tests must be performed:
- PCR (Polymerase Chain Reaction): these are the swabs you’ve been hearing about and the vast majority of tests currently being conducted, but only on the sickest of patients. By doing a PCR on everyone, we can get a good indication of the real % of the population that has the virus, and more importantly, how many of those positive cases are mild/asymptomatic. When we first started doing these tests, it was taking days for results, but there are a number of companies that have already shortened that time frame to hours.
- Serological: these are blood tests that screen for antibodies which become present in the later stages of the virus and remain present after you have already recovered. Serological testing is the only way to understand how many of us already had the coronavirus in the past few months. This test is much simpler than PCR in practice (requires a little finger prick) and the results are known in a matter of minutes.
Currently, we are only testing the sickest among us, and only doing PCR testing. That is giving us bad information (garbage in) that we are using to make potentially bad decisions with severe long-term consequences (garbage out).
As of March 28, 735,704 people in the U.S. have been PCR-tested for COVID-19 (0.2% of the population) with 118,234 positive results and 1,965 deaths (source). That means 16% of tests are positive with 1.7% of the positive cases resulting in death.
These facts are better to have than not to have, but are woefully incomplete and presenting a distorted version of reality. They tell us nothing about…
a) the number of people who have had the virus and already recovered, now showing a negative PCR result,
b) the number of people with active infections that have moderate, mild, or no symptoms at all (and not being tested), and
c) the number of people in the broader population who have neither had the virus yet nor are active carriers (how widespread the virus is).
Let’s break down why each of these pieces of information are vitally important.
A) Already Recovered
The first positive case of the COVID-19 in China is thought to date back to November 17, 2019. Between then and the travel restrictions from China to the U.S. announced on January 31, 2020, there were at least 600,000 visitors from China to the U.S. (based on tourism estimates of close to 3 million visitors per year).
That is more than enough people and more than enough time for cases to have already spread widely across the U.S. by January and February. That mild cold you had a month ago? It could very well have been the coronavirus. And how many countless people already had it with no symptoms at all?
We’ll only know the answer through serological testing, but in places like New York with more frequent travel from China and Europe, it was likely present far earlier and spread far wider than anyone could imagine.
Knowing just how many people have already recovered from COVID-19 will give us better information about the real denominator (# of positive cases) and the true fatality rate. It will also allow us to know who can safely start living their lives gain, as they now have immunity. And potentially, we can start using the antibody-rich blood from the immune to help treat the most severe active cases (trials are already underway).
B) Active Infections With No/Mild/Moderate Symptoms
Part of what makes COVID-19 such an easily transmissible virus is the huge number of cases showing no symptoms at all, or extremely mild symptoms akin to the common cold.
If you don’t have any symptoms, you’re not going to go out and get tested (especially when you’re being told to stay home and you won’t be given a test even if you want one), and can be a carrier to others. Vo, Italy and Iceland have had success in isolating these asymptomatic carriers, reducing the rate of spread.
Knowing how many people are in this bucket will add to the denominator (again, help determine the true fatality rate) and give us better information on who should be isolated from those most at risk.
C) The Difference: Everyone Else
Up until now, we’ve been ignoring a potentially enormous part of the equation: those who have not yet contracted the virus and are not actively infected.
What this number is no one knows. Is it 99%, 95%, or something much lower (implying the virus has already spread more widely than anyone has predicted and is therefore more benign than anyone is saying)? During the H1N1 pandemic in 2009-10, we estimated after-the-fact that nearly 61 million Americans, roughly 1 in 5, had contracted the disease. If the same is true today, it means like the H1N1, COVID-19 is not nearly as deadly as initially thought.
In Iceland, 1% of the broad population has tested positive thus far. In Vo, Italy where they tested everyone, 3% tested positive. However, both of these numbers could very well be understating the true spread as they have not done serological testing.
Getting Closer to the Truth
It is not unreasonable as a starting point to assume that 1-3% of the U.S. currently has the virus (from Iceland/Vo), meaning 3.3 million to 9.9 million Americans. If that is indeed the case, then the current death rate of 1.7% would move down to .06% or .02%.
These fatality rates will likely increase as the number of deaths increase in the coming weeks/months (deaths are a lagging indicator), but in any scenario the true fatality rate is likely a fraction of the current estimated fatality rate.
What that fraction is (1/2, 1/3, 1/5, 1/10, etc.) we’ll only know through random sampling of the population at large.
Is it possible that the true denominator is larger than 1-3% if we include serological testing of those already recovered?
Yes.
Thus far in the U.S. there is a mid-range estimate of 46 million seasonal flu infections (source: CDC). We estimate this number not from counting every person, but by using sampling and mathematical models. From the roughly 1.2 million flu tests we have conducted in 10 regions throughout the country, we found approximately 242,000 positive results (20% positive). And from those 242,000 positive results we estimate 46 million Americans have had the flu this year (14% of the population) with 43,000 deaths (fatality rate of .09%).
As it is widely believed that the novel coronavirus spreads much more easily than the seasonal flu, and was likely here in the US since last November/December, there very well could be millions of cases that we are not counting.
Needless to say, if there are already millions or tens of millions cases of COVID-19 in the U.S., a change in our draconian approach might be warranted.
How Any Town in America Could Save the World
If we continue with the current policy of shutting down the entire economy, we are headed for a global Depression and a breakdown in society as we know it. If this were the plague (30%-60% of population dies), that might be a risk we would have to take.
But a plague this is not, and if we keep acting like it is, billions around the world will suffer negative consequences, with many more lives lost than from this virus.
We are wasting valuable time. Millions of American jobs were lost last week, and will continue to be lost every week that we wait.
We need to not only test more, but test smarter. The “test, test, test” mantra needs to shift to “sample, sample, sample.” We do this with the seasonal flu each year and given its spread, we need to do the same with COVID-19.
That starts with picking any town in America and testing everyone (PCR & Serological). The suburbs of New York are a good starting point (densely populated areas where broad testing could be done more swiftly and efficiently than other areas) and we could quickly do the same across other hot spots in the country (New Jersey, Washington, California, etc.). The tests should be repeated every two weeks to track the progression.
The data from these tests would finally give us a clearer picture of what we’re actually dealing with and how best to proceed.
I’m optimistic that this will happen soon as the stakes of not doing so are simply too high. Anytown, USA can indeed save the world. Let’s mobilize the effort and start today. Please spread the word and help contact the powers that be. Our future depends on it.
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