What is up with this virus, just fascinating patterns. Very hard to disentangle–what is due to characteristics of the virus, as it interacts with the environment it finds itself in and how that environment changes; what is due to change in human biochemistry as the environment changes; and what is due to human behavior changes, largely around perceptions of more or less risk. I am trying hard to find everything I can related to this subject, don’t think there are really clear answers yet, but there very clearly is some complex geographic/seasonal effect. I am used to most things in this world being more complex than appears on the surface, but this pattern for spread is truly governed by some very complicated formula. And it appears to have some very delicate tipping point at which transmission becomes far easier and spread increases rapidly. But then equally baffling is why it appears to last roughly the same time in each surge in each place and then diminish quickly to a long tail. I believe that is exactly what we are seeing now in the Upper Midwest. The chart I posted a few days ago on the midwestern states showed in most states those very similar curves of rapid growth, a steep increase over a short time, then a brief pause in growth at the top, and a pretty steep drop down. The steepness of the up-curve suggests a very infectious pathogen, easily transmitted. I suspect this is some combination of low dose needed to infect and some hardiness, lingering ability of the virus in the environment, especially indoors. It would also be interesting to have enough cycle number data on PCR tests to see the case curve only for cases with a cycle number of 30 or under for example. Would that curve look substantially different? Is the pause caused predominantly by enough people being infected to slow transmission opportunities? Does voluntary behavior change as people become aware of the case surge have a significant impact. The rapid drop is largely due to the steepness of the ramp up–once the turn around begins, very large number of cases rapidly stop becoming infectious, so the number of transmitters is declining very quickly. The latest research indicates that people are truly infectious for a very short time–maybe a week at most.
From a government policy side, what is notable of course is the complete unwillingness to shape policy based on this very apparent case wave pattern. So called public health experts see a case wave start and begin talking about a long, dark winter. Our usual incompetent modeling sources start predicting humongous numbers of cases and deaths. Press hysteria mounts. And politicians, instead of asking questions and seeking alternative viewpoints, just blindly follow the herd and order more shutdowns and truly draconian, or as the NY Times referred to them, “bizarre and unscientific” bans on social gatherings, even in people’s private homes. Then of course, when the usual pattern prevails and even though the top clearly appeared before any of these orders could have had an impact, they will attempt to take a victory lap based on these orders that had no impact on case spread. So it is Minnesota, so it is across the country except in a couple of enlightened jurisdictions like Florida. Don’t get fooled again.