Testing the Mild Cases & Today’s COVID-19 Report | Wed May 13

To prevent COVID-19 from spreading to family, friends, and the community, Public Health – Seattle & King County recommends that anyone with symptoms or who has been in close contact with someone who has COVID-19 be tested right away.

Previously, due to supply shortages, health officials prioritized testing for people most at risk for severe illness – including healthcare providers and first responders. Now, the Washington State Department of Health has expanded the criteria for who should be tested, and supplies of testing kits and personal protective equipment are increasing.

Also, lower numbers of COVID-19 cases in long-term care facilities point to the importance of public health measures in reducing the spread of the virus in these settings.  Further details are all available in today’s update on the Public Health Insider.

Otherwise, this daily synthesis of the Public Health data is provided by Will Daugherty of Pacific Science Center.  Thanks Will!

Public Health has updated the data dashboard.  As of 11:59 pm yesterday, May 12, there were 7,221 confirmed cases of COVID-19 in King County, 42 more than the previous day.  There have been 514 confirmed deaths in King County due to COVID-19, 7.1% of all confirmed cases.

The numbers that Public Health reports each day include delayed results from previous days. 

Observations

The three graphs below chart new cases, total case count and the logarithmic trajectory of cases.

The first graph shows new cases (blue bars) and the 7-day average (red line).  Of the 42 cases reported today, 23 were confirmed yesterday and the remaining 19 were confirmed in previous days.  The 7-day average of new cases per day peaked at 191 on April 1.  After flattening for a few days last week, the steady downward trajectory has resumed and the average for the last 7 days is down to 63 new cases per day.

The second graph shows the total case count.  With 7,221 total cases as of 11:59 pm yesterday, the compound daily growth rate during the last 7 days has been 0.9%, slightly less than the 1.2% rate during the prior 7 days.  If we start with 7,221 cases, a 0.9% compound daily growth rate (0.898% to be precise) yields 65 new cases in a day, 466 new cases in a week, and 2,054 new cases in four weeks.  With 7,221 cases, the compound daily growth rate will must be less than 0.138% in order for the number of new cases per day to be less than 10.

The third graph shows the trajectory of cases in King County with the total number of cases on the horizontal axis and the new cases on the vertical axis.  Each axis is on a logarithmic scale.  Each blue dot represents a daily report.  The dot farthest to the left is the February 28 report.  Time passes from left to right as the total case count grows.  The dot farthest to the right is today’s daily report.  We can see a clear change in the trajectory since March 28, shortly after Governor Inslee’s “Stay Home, Stay Healthy” order on March 23.

Will Daugherty welcomes your questions and comments.  His email is wdaugherty@pacsci.org