[Daily Plot at bottom added 4/17]
As countries around the world have implemented social distancing, they have seen an exponential decrease in their daily case growth rates, each likely reflecting their distancing practices. This pattern can be used to project estimates of how cases and deaths will progress in the US in the coming weeks and months.
The daily reduction in a sampling of countries is shown below. The USA case growth rate is dropping 8.3%/day. Italy dropped their rate at 7.7% per day. while Spain dropped 12%. South Korea has averaged -11.8% per day with a pause from day 20 to 35 in the downward trend. China steadily dropped their case growth rate 15% a day from the start of their lockdown.
This trend in the United States case growth rate can be used to project estimates of how social distancing will be reflected in the growth of cases and deaths in the US going forward.
This basic model predicts we will see peak rates of death around April 15th at around 2040 per day.
If this trend continues we could see identified cases plateau around 1 million and deaths rise to “only” 62,000. If the United States had not implemented social distancing that level may have been reached by April 11th with potentially a million dead before the end of the month.
Whether we follow these trends in the long term depends on how effective we are in maintaining or enhancing social distancing. China was able to drop their case growth rate twice as fast.