Monday, March 30, 2020

Coronavirus dashboard for March 30: exponential growth rate may be decreasing


 - by New Deal democrat

Here is the update through yesterday (March 29) 

I am pleased to read that it looks like there is near-consensus in the medical community that a “first China, then South Korea”  (or, “Sledgehammer then Scalpel”) approach is the paradigm to tamp down the pandemic. 

Over 50% of the US population is now under lockdown, and it may be beginning to break the band of exponential growth.

Based on South Korea’s experience, a ratio of 15:1 in total tests to results showing infection is the level where there can be some confidence that the infections have been contained. I pointed that out to Bill McBride a week ago, and he is now including that in his daily testing graphs. Testing in the past 4 days has plateaued (not good) and is not keeping pace at all with the growth in new infections.

The above three most important metrics are starred (***) below. 


Number and rate of increase of Reported Infections (from Johns Hopkins via arcgis.com)
  • Number: up +18,369 to 143,055 (vs. +19,849 on March 28)
  • ***Rate of increase: day/day: 15% (vs. 34.6% baseline, 22% for the past week, and 19% on March 27)
There’s an excellent video up, showing how comparing the 7 day rates of growth in new vs. total infections can show when the exponential rate of growth is beginning to slow. We may have just arrived at that point. 
Note: Ben Engebreth, whose Department of Numbers used to track house prices back in the housing bubble days, has started tracking coronvirus infection and testing numbers, with graphs. You can find it here.
Number and rate of increase of testing (from COVID Tracking Project)
  • Number: 95,647, down -13,424 vs. 109,071 on March 28 day/day
  • Rate: decrease of -12% vs. number of tests previous day
Comparison of rates of increase in documented infections vs. testing  
  • Infections +15% vs. Tests -12% day/day
Result: The rate of testing is failing to improve and is far, far below what is needed, which is probably now at least 200,000/day. Note this target number is also increasing exponentially as we try to chase the number of exponentially increasing infections.

Ratio of tests to positives for infection (from COVID Tracking Project)
  • Number: 95,647 new tests vs. 20,827 new diagnosed infections 
  • ***Ratio: 4.6:1 
In South Korea, where aggressive testing has led to a near-total disappearance of new cases, the inflection point where the number of new daily cases plateaued was reached when the ratio of tests to new cases found reached 15:1. Any ratio less than that suggests that not enough testing is being done. Yesterday’s ratio of 4.6:1 continues the trend of  worsening, I.e., we are falling further and further behind in testing.
Number of States (+DC and Puerto Rico) in total lockdown, business lockdown, and partial restrictions
  • Total lockdown (personal + business): 26 (AK, CA, CO, CT, DE, HI, ID, IL, IN, KS, LA, MN, NC, NH, NM, MI, MT, NJ, NY, OH, OR, PR, RI, VT, WA, WI, WV)
  • Business lockdown: 7 (DC, KY, MA, MD, ME*, NV, PA*)
  • Partial restrictions on business (restaurants and bars): 14 (AL, FL*^, GA*, IA, MO*, MS, ND, SC*, TN*, TX*^, UT*, VA, WY) 
  • School closure only: 4 (AZ**, AR, OK**, SD)  
  • No mandatory restrictions: 1 (NE*) 
*some local areas are under lockdowns
**some local areas with partial restrictions
^restrictions on entry into State from some other affected States
With the exception of Arizona, all of the remaining States with no restrictions or only school closures are rural.
Number and percent of US population in total lockdown, business lockdown, and partial restrictions
  • ***Total lockdown: 153.2 million, 46.2% 
  • ***Business lockdown: 39.2 million, 11.8%
  • Partial restrictions on business (bars, restaurants): 103.3 million, 31.1% 
  • School closure only: 12.8 million, 3.9% 
  • No mandatory restrictions: 1.9 million, 0.6%
Earlier last week, there was a decisive move towards more restrictive measures across the board. This all but ground to a halt across the southern “red” States. Continued exponential growth in those cases will teach a brutal lesson.
Over half of the total US population, including metro areas in some non-lockdown States,  is under total lockdown. That is the percentage, AT MINIMUM, I think we need to have a chance of following China’s successful strategy for beating back the pandemic. 
The deceleration of the rate of increase in new cases may be the first signs that “social distancing” is bearing some limited fruit. But a deceleration in the exponential rate of increase still means the US as a whole is failing.
Further, the rate of testing, while having increased tremendously, still remains abysmally too low compared with the spread of the virus. In other words, we are still chasing the virus, and we are falling further behind.
There is NO HOPE that the federal government under Trump will take necessary steps - in particular, enforcing a nationwide lockdown or assisting the States in theirs, or ordering production of masks, tests, thermometers or other necessary equipment.  Therefore those States which have gone to lockdowns need to cooperate regionally in quarantining incoming visitors at airports, train stations and at highway checkpoints.