In a previous blog on my website (drquay.com/covid-19-update-2320-gmt-21-mar/) I described a proprietary toll I developed to provide a snapshot, a single moment in time, in the status of this battle. Based on how China and South Korea were able to declare victory (although pockets of fighting continue) the Days to a Ten-Fold Growth in case number (DTFG) is a predictive tool as to whom is winning. I have color coded the chart below and given the definition of each scoring possibility. Countries have four conditions: human victory, humans winning, a virus-human stalemate, and virus winning. I saw no reason to have a category of virus victory, at this time.
The scoreboard as of the time above:
Two countries have declared victory and two countries are winning.
There is a group of nine countries in which the virus and the humans are at a stalemate. Now, while it is always better to be winning, a stalemate is a good thing because, in almost all cases, the virus starts out on offensive, gets the ball first, and spends a week or two winning, moving the case number up quickly, marching down the field. So in American football terms, a stalemate is when the forward progress of the virus has been stopped and the virus has to kick on fourth down.
I welcome my international friends and colleagues to provide soccer or rugby analogies.
Also, not all stalemates are created equal. Sweden with a stalemate at about 1900 cases and Spain with a stalemate at over 33,000 are VERY different public health resource problems and disruption of life issues. The way to think about it is, with a stalemate, you will have a two-fold to four-fold increase in cases from where you are before you can declare victory. But this example is a difference of tens of thousands of cases.
A short two weeks ago (Mar 7) over 95% of all cases in the world were in four countries: China, South Korea, Iran, and Italy. For many complex reasons, the medical response and societal response of each country differed. And of course one cannot look to the future without pausing to contemplate the devastation these four countries have experienced. But the good news is that, at least at the present time, all four of these countries are either winning or have declared victory. And because they got there by ‘different histories’ there seems to be a ‘yet to be understood’ factor that ends up putting a brake on absolute, exponential growth.
In five countries the virus is winning. In four of those the case number is low. This is like a team scoring on the first possession of the ball. If these countries can get to a DTFG above 10 in the next few days, they may end up looking like Switzerland or the UK. I think their window to end up like Sweden has passed.
The US trend line makes it impossible to know where it will level off but it is highly likely it will be above China’s eighty thousand cases.
In a future blog I will lay out the data so you can make your own assessment but my conclusion is that there are three critical factors to change the dynamic to humans winning in this pandemic: frontier control to isolate pockets of cases and keep them from spreading (<10% of cases in China were outside the frontier lockdown of Hubei province, where Wuhan is located); shelter-in-place or social distancing to slow local spread (in Wuhan, <1% of the local population became infected); and virus testing to quickly find cases. Of these, virus testing is the least important.
Symptoms appear at five days, the virus test cannot pick up an infection before three days, and so spreading will occur during the symptom-free period in most patients or at any time in the one in five who have no symptoms (and when tested are equivocally positive) but can spread the disease.
Social distancing and frontier control, lock down, are what determine success.
The Twitter version of testing is: in a society that has universal symptom-based virus testing but the population are free-range humans, the virus will always win.