SARS-CoV-2 versus The Humans: A Country by Country Analysis of Who’s Winning
Summary: A tool has been developed to determine whether the virus, SARS-CoV-2, or the residents of a given country, are winning in this pandemic. It measures how many days it takes for a ten-fold increase or one logarithm, in cases. For example, going from 10 to 100 or 1,000 to 10,000.
The tool is called Days to Ten-Fold Growth or abbreviated DTFG.
The tool is based on what happened in China and South Korea, the only countries in which the humans can “probably” declare victory. Here is how it works.
A DTFG of <10, that is, the virus is increasing ten-fold in less than 10 days means the virus is winning. A DTFG of 10-15 is a stalemate, no one is winning but both sides are fighting, neither the virus nor the humans are advancing. A DTFG of 15 to 24 means the humans are winning. In China and South Korea, where the humans have declared victory, the DTFG is now >24; it takes longer than 24 days for a ten-fold increase. There are still pockets of fighting going on but things are relatively normal.
So what is the score at the time I am writing this blog:
When China had between 10,000 and 30,000 cases, in the ‘zone’ as I call it, they were at a stalemate. China went on to win but the virus infected about 80,000 in total before they could declare victory.
France, Iran, and Italy are in the zone now, are doing well, and should end up with fewer than 80,000 cases. Italy is at a stalemate, like China was, so they need to transition to winning.
Sweden is also at a stalemate but with only 1770 cases, compared to Italy’s over 53,000, Sweden has the potential to transition from a stalemate to winning with significantly lower case numbers.
Spain and the United States are both in the zone and losing to the virus, and will probably end up with more than 80,000 cases. United Kingdom is not yet in the zone and so, if handled properly, could end up with fewer than 80,000 cases.
I imagined a ‘Perfect Land,’ where the medical scientists are always vigilant, the government makes public health policy decisions its first priority and doesn’t care if its decisions are unpopular, they have military-level control over their residents, and the residents will be obedient to the government, and if asked to quarantine for 14 days will be 100% compliant.
Perfect Land identified the new virus when there were <10 cases and locked down the country one week later. Repeating, they locked down an entire country when there were 10 cases! Perfect Land declared victory at about 7,000 cases. Since none of us live in Perfect Land, we should not beat ourselves up over the way we are handling this virus.
Humans will prevail but this virus is one of the fastest spreading microbes every witnessed.
My thinking and analysis to come up with the DTFG tool
To look at how a country’s response to a viral pandemic is working, is the virus winning or are we humans on top, requires that we drop into the ‘mind’ and behavior of SARS-CoV-2, that 30,000 letter, twenty page pamphlet that is being so tough on humans.
Why can’t we think exponentially? It is probably because, as we shuffle off this mortal coil, we don’t live long enough to see beyond two or three generations of ancestors and descendants. Hobby tip: doing family history helps a little as you begin to realize that you have over 8,000 great grandparents in about the year 1600.
Back to the virus. A trick we humans can do is to plot the growth in cases over time on a special scale, where the equal spacing on the Y-axis is 10, 100, 1000, 10,000, etc. As crazy as it might seem, pandemics are a straight line when plotted this way. At that point, you can measure the time for each log growth to occur. From the virus’s perspective it will take the same time to go from 10 cases to 100, as it takes from 1,000 to 10,000, and so on. Finally, at some point the line stops being straight and ‘flops over’ as I like to say. This is when it runs out of humans to infect, the humans disappear into their houses, and stop travelling, etc.
Now to my chart. I looked at 10 real countries and how they have responded to the virus and collected data.
Based on this analysis I also created what I call ‘Perfect Land,’ an imaginary place where the doctors never make a mistake, there are no delays, scientists can see the future, government has perfect timing and formulates the perfect policies, and the citizens are 100% obedient to their government.
Please no political comments on which real country most resembles Perfect Land! 🙂
The data I collected was how long the virus took to grow from each 10-fold of patients. So how long from patient 1 to patient 10, how long from patient 10 to patient 100, how long from patient 100 to 1,000, how long from 1,000 to 10,000. Because China is the only country to get over 30,000 cases but were able to stop at about 80,000, I thought it was important to see what China was doing when they had between 10,000 and 30,000 patients, where the US and the other high case number countries are at the time of this writing.
I saw a few patterns in the data and I decided to color code them to make it easy to see patterns.
The most out of control growth for this virus is a ‘log growth’ of <10 days; going from 100, say, to 1,000 in <10 days. Basically, the virus is spreading at its maximum rate and the humans are doing nothing; haven’t responded yet. I gave this growth rate a red color. The red color means ‘THE VIRUS IS WINNING.’
I saw another growth rate that clustered between 10 and 15 days to grow 10-fold. Here is virus is struggling for reasons, maybe unknown, and the humans are starting to respond. Since I saw countries go from this rate go both ways (some get better and some get worse) I labelled this yellow, which means the virus and humans are at a ‘STALEMATE.’
Finally, either as the virus is just getting into a country, at the beginning, or much later, when the humans are winning, the 10-fold growth rate is 15-30. I picked 24 for this cut off because the two countries that seem to have won completely, are running at a >24 days per 10-fold growth. As you can figure out, if the virus is gone this number will gradually grow all the way to infinity.
I also thought it was important to get an ‘instantaneous rate’ of the last data point today from the WHO and use that to project into the future. So the values that are not true 10-fold growth numbers have a T by them to signal they are a terminal growth rate. Taking the number of cases on the latest day, dividing that number by ten, and counting back to get a 10-fold, backward looking, growth rate.
Okay, let’s see what SARS-CoV-2 does in Perfect Land. The virus appears out of nowhere and 10 citizens of Perfect Land can see the future growth and they announce a policy to Lock Down the country. The policy is rolled out and is fully in place in one week, seven days. The citizen’s cooperate. Using data from China and South Korea, if Perfect Land locks down the country when there are 10 cases they will end up with about 7,000 cases.