Mid-August Corona Data Update

Here’s the three-month trend in estimated Rt, the virus’s effective reproduction rate in the US, calculated as the average daily death count during the past ten days divided by the daily death count for the preceding ten-day interval:

  • August 11 – August 21:  1,103/980 = 1.13
  • August 1 – August 11:  980/1,118 = 0.88
  • July 22 – August 1:   1,118/843 = 1.33
  • July 12 – July 22:   843/633 = 1.33
  • July 2 – July 12:   633/630 = 1.00
  • June 22 – July 2:    630/599 = 1.05
  • June 12 – June 22:   599/853 = 0.70
  • June 2 – June 12:   853/940 = 0.91
  • May 23 – June 2:   940/1,316 = 0.71
  • May 13 – May 23:   1,316/1,700 = 0.77

While the daily death count has plateaued over the past twenty days, the daily case count has dropped:

  • August 11 – August 21:  48.6/53.9 = 0.90
  • August 1 – August 11:  53.9/66.6 = 0.81

Death is a lagging indicator, so presumably the decrease in cases portends a decrease in deaths. Test-positive percentages have also been in decline; however, the overall testing rate too has dropped. An educated guess: the daily death counts will decrease incrementally over the upcoming ten days, while remaining substantially higher than they were two months ago.

How many people have been infected in the US? Recently I increased the estimated infection fatality rate from 0.6% to 0.85%. Divide total death count by fatality rate to estimate total infections: 179,200/.085 = 21.1 million, or about 6.5 percent of the US population. In my state of North Carolina there have been 2,531 corona-related deaths, which computes to around 4 percent of the state population having been infected.

 

2 thoughts on “Mid-August Corona Data Update

    1. Indeed. That’s the implication of a higher fatality rate: a lower estimated prevalence. 328 million Americans x 75% infection rate x 0.85% fatality rate = 2.1 million dead to reach herd immunity.

      Like

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s