The effect of the Wuhan coronavirus epidemic is obvious. It is accepted that at some point the economy will have to resume, and that it is unreasonable, and frankly stupid to suggest, that the condition for doing so is that the daily number of new cases be zero. There is however understandable official reluctance to proceed with the loosening of social distancing practices that resuming economic activity necessarily entails. There are a couple of reasons for this.
One, there is a virtue auction going on. No politician wants to be seen as saying the number of old folks dying is "acceptable," that is, low enough to justify resuming economic activity. The auction occurs when politician A declares that the number of deaths, while tragic, regrettable, etc., is such that it is reasonable to loosen things up, politician B bids a lower number of deaths, to show that he cares more. It is a little like the meetings in the Soviet Union where politicians were unwilling to be the first to stop applauding the introduction of Stalin. Politicians do not want to be the first to say that some non-zero number of deaths is an acceptable trade off for letting people get on with their lives. This goes on until the people themselves decide that economic concerns predominate and pressure political leaders to change focus.
A second issue is that there is a fair amount of uncertainty as to what will happen regarding spread of infection if restrictions are relaxed in deference to economic concerns. The whole concept of "flattening the curve" seems to adopt a notion that nearly everyone will eventually get infected, and the idea is simply to control the rate at which that occurs. Dr. Fauci seems to subscribe to this view, and it relies on an assumption that everyone has more or less the same susceptibility to the disease. It includes that assumption that any loosening of restrictions and social distancing will result in uncontrolled spread of infection. This view however is more consistent with risk aversion and worst case scenarios than with actual experience.
Another model assumes that if restriction are held in place, the total number of cases will be less when the epidemic has ended. A third model, that discussed in these posts suggests that when restrictions are loosened, the will be an uptick in the spread of the virus, but this will be limited, as a new point of equilibrium is reached.
Each of these models has implications on a fundamental question: do the restrictions intended to control spread of the virus do any good?
The first model assumes that everyone will eventually get infected, but that the number of deaths will be limited somewhat because the rate of spread will permit the provision of medical services to people who might otherwise die without them. To determine if this makes sense, it is necessary to know how many people who receive medical care die anyway. How many people who survive mechanical ventilation would not have been placed on a ventilator if the spread of the virus were less constrained? What was the pre-virus life expectancy of these people?
The second model limits the absolute number of cases and consequently the resulting number of deaths. This implicitly rejects the notion that everyone will get infected. It also necessarily contemplates some mechanism by which the virus disappears. The difficulty with this model is that amount by which the ultimate number of cases is reduced is unknown, and also unknowable. The same considerations that apply to the first model also apply to this one. The reality is that it is unreasonable to freeze all activity except waiting for the number of new daily cases to drop to zero. Adopting this model may result in fewer deaths, it may not.
The third model, the one that considers that the rate of spread is limited because of two readily observable conditions, decrease in the rate of infection over time and previously infected people becoming no longer capable of spreading the infection, suggests that when disease mitigation efforts are relaxed, the rates of infection will increase to a new equilibrium point then stabilize. It suggests that not everyone will become infected. It does allow that the rate of spread can be controlled to some degree, as the mitigation efforts determine a particular point of equilibrium, which changes when the mitigation efforts change. This model thus supports a brief period of mitigation efforts, to avoid overwhelming the medical system, predicts a modest uptick in disease activity as a new equilibrium is reached, but also highlights the diminishing returns of prolonging mitigation efforts.
Given this, and assuming that the third model is the most predictive (an assumption based on observation, not rigorous scientific proof), a reasonable way to open up the economy would be, proceeding at the state level, in three day increments:
1. Make mitigation efforts, including masks and travel restrictions voluntary, but highly recommended.
2. Allow low risk enterprises, specifically landscaping, roofing, construction, hair salons, and infrastructure work to resume.
3.Remove restrictions on "non-essential" business, again highly recommending people adhere to prudent infection control practices.
4. Allow restaurants and bars to re-open with modifications such as hand sanitizer and wipes at each table, use of disposable menus, hand santizer outside of the restrooms, use of disposable pre-wrapped utensils, etc.
5. Allow all businesses except nursing homes, skilled nursing facilities and rehab hospitals to resume operations. Health departments should use local patterns of infection to determine when restrictions in these types of facilities, i.e. visitors, use of N95 masks and so on, can be relaxed.
The criteria for when to begin doing this should be when the average number of daily new cases is some fraction of the peak number of new cases, say 40%.
Schools should be allowed to re-open according to a more stringent criteria, say when the ration of new to peak cases is 25%.
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