Thread by @bansisharma

1. Case Against Wholesale Lockdown

There are honest differences of opinion between those advocating for a wholesale national lockdown, or alternatively broad-scale regional lockdowns, and those advocating for minimalist and/or no lockdowns but only diligent mitigation measures.

2. Both sides have their hearts and minds in the right place. I believe the difference is predominantly in the the underlying assumptions each side makes. I have vacillated between the two sides as new information emerges.

3. In this thread I will make the case against lockdowns and explicitly state the assumptions the case is based on. If the assumptions are false, then the conclusion will be false too. I intend to catalyze a discussion about the assumptions, not about the conclusion.

4. Assumption#1: The cat is already out of the bag in most countries showing significant number of infections, including the US of course. Containing the infection completely is now out of the question. We are mitigating to slow down the rate of spread so as to flatten the curve.

5. Assumption#2: Flattening the curve is all about making sure the number of hospitalizations of severe cases stay below hospital capacity, i.e. if we slow down the number of hospital admissions to no more than discharges (after capacity expansion), we will cope adequately.

6. Assumption#3: Coronavirus spreads fast but is not lethal or even severely unpleasant to most of the population, certainly a lot less risky for non-elderly healthy individuals than previous widespread viruses like H1N1.

7. Assumption#4: Lockdown or no lockdown, we absolutely need to protect the elderly and immunocompromised through isolation in all scenarios. So we should take that as a given, and out of the equation of discussion on the necessity for lockdowns.

8. Assumption#5: Ultimately, a large portion of the population (excluding the elderly and the immunocompromised, if we do it right), maybe even as large as 50+%, will get infected. It is only a matter of time. Vast majority will thereby develop immunity. The only way it will end.

9. Assumption#6: Not opening up the economy as soon as possible without undue risk (undue risk being defined as development of severe cases that are likely to outrun hospital capacity) is counter-productive as it will cause relatively more non-virus related misery and deaths.

10. That is it for the assumptions. The case for lockdowns is based mostly on the justifiable scare from Italy and the original Neil Ferguson model projecting 250,000 deaths in the UK and millions of deaths in the US.

11. Ferguson has now admitted that his projections were based on an unlikely scenario which ascribed a much higher degree of lethality to coronavirus than seems to be the case, because it is far more widespread already than he assumed in his model.

12. Ferguson states in his revised report that the number of deaths in the UK are more likely to be of the order of 20,000 instead of 250,000 and more than half of those deaths (mostly among the elderly with pre-existing conditions) would occur this year even without coronavirus.

13. Based and Ferguson's revised projections, UK now believes it has adequate hospital capacity to deal with severe coronavirus cases. Consequently, last week, UK reduced the threat level associated with coronavirus.

14. But what about New York City, and other metropolitan areas in the US which are showing an alarming level of increase in cases, fatalities, and hospital admissions? Of course they are alarming, and we need to do whatever it takes to bend the curve there.

15. However, there was one very important piece of news from Dr. Deborah Birx on today's Presidential Task Force Briefing. She mentioned that they are revising their projection models for number of ventilators needed in big cities around the nation based on the fact that ...

16. ... previous projection models did not take into account the fact that the current hospitalizations are caused by infections contracted before the President's "15 Days to Slow the Spread" mitigation strategy went into effect.

17. Number of deaths is likely to continue to rise for the next two weeks, because we are dealing with a pipeline of unfettered infections that happened about a month ago. If true, the number of severe cases should begin to climb down in the next two to three weeks.

18. If we indeed see the severe cases in all metropolitan areas across the nation receding in 3 weeks, it would indicate that the current mitigation strategy, coupled with large scale, widespread availability of testing may be sufficient to consider re-opening the economy slowly.

19. Of course the next three weeks will be crucial and a period of maximum uncertainty as theory meets reality. No doubt the reality will have to trump the theory, no matter which way it goes. Meanwhile, here is hoping we turn the corner in the next two weeks.

The End