What did the massive and disruptive effort to engage in physical distancing during the last two weeks of March and all of April buy?
I think it bought a lot of health against a counterfactual of unconstrained spread.
The first thing April bought was several doublings that did not happen:
Update on #Covid19 cases, 5/3
— Timothy McBride (@mcbridetd) May 3, 2020
Over the course of the month, cases increased by slightly more a factor of four, or two doublings. That implies an average doubling rate of 15 days. In March and early April, a doubling in case count was happening every three to five days. So physical distancing bought at least four doublings avoided. And that probably means we bought the hospitals a chance in hell of not being overwhelmed.
Case count is still growing which means the (R)eproductive rate is still above 1.
Excluding the New York tristate area, national covid19 infections, hospitalizations, and deaths continue to increase. The national doubling time has rise to about 25 days, but the epidemic continues to slowly expand. And covid spread – although slower – remains persistent. pic.twitter.com/isse2NRvpA
— Scott Gottlieb, MD (@ScottGottliebMD) May 3, 2020
The doubling time is almost to a month. That is not good as we want doubling to cease and active case counts to shrink, but compared to mid-March, this is a vast improvement.
The next thing that April bought is time to get testing to approach the scale that is needed.
Our daily update is published. We’ve now tracked 6.6 million tests, up ~321k from yesterday, a new single-day record.
Note that we can only track tests that a state reports.
— The COVID Tracking Project (@COVID19Tracking) May 1, 2020
We’re not quite there. The lowest level of testing needed for effective public health interventions at the individual level instead of community level is 3 million or more tests per week or an average of 430,000 test per day. We’re not there yet, but it is starting to get to the point of being plausible.
Finally, the trial for an anti-viral that has no proven mortality effect but shortens hospital stays effectively creates several hundred thousand bed days out of thin air as well as trained individuals to staff those beds. April bought learning from both overwhelmed hospital systems in metro New York City as well as from systems that are not being overwhelmed. New techniques and procedures are being tested, evaluated and disseminated to clinicians who have enough time and mental energy to learn instead of fighting fires with a garden hose.
April did not buy us everything. Ideally, April would have seen R rates well under 1 for several weeks to dramatically cut back on the infectious base as states and people begin to loosen up formal and personal movement restrictions, but compared to a counterfactual where nothing happened in April, April bought us a lot.