Although the US is continuing to hit records for daily #COVID19 cases reported, the rate of exponential growth has slowed. Mortality is still catching up to increased case loads and I expect daily deaths reported to further increase. 1/8
This plot summarizes the overall picture. Bubble size is proportional to daily cases per capita from @COVID19Tracking and bubble color shows Rt from rt.live. Timepoints are shown up to two weeks ago due to delay in reliable estimates of Rt. 2/8
The Midwest and Mountain West had rapid growth during October resulting in large epidemics in November, but they're now starting to plateau or decline in incidence. Although current incidence is lower, the epidemic is still growing in much of the East Coast. 3/8
These trends can be seen in time series of state-level case counts. Plotting these on a log scale highlights exponential growth as straight lines. Some states have begun to decline (ND, WI), some have plateaued (CO, MI) and others are still growing (CA, AZ, NY). 4/8
Overall, exponential growth of cases in the US has slowed considerably. However, going forwards it remains to be seen whether there will be significant reduction in circulation instead of a plateau. 5/8
After a Thanksgiving reporting dip, the 22-day lagged case fatality rate (CFR) is now ~1.5%. 6/8
The lookahead projection of converting 1.7% of reported cases to reported deaths 22-days later has remained largely predictive, although it's been slightly over-predicting deaths this past week. 7/8
Still, I expect the 7-day average of daily reported deaths to continue to climb in the next 3 weeks to reflect case loads that are higher today than they were ~22 days ago. 8/8
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The US reported over 3000 deaths from #COVID19 today and the 7-day average of deaths has hit a record with today's average of 2276. Here, I dig into these grim mortality numbers and look at deaths across ages and across weeks in the epidemic. 1/14
I'm using data from @CDCgov (cdc.gov/nchs/nvss/vsrr…) that records weekly deaths involving COVID-19 as well as deaths from all causes. These data use actual date of death but there is a reporting lag. 2/14
CDC reports 261k deaths involving COVID-19 in this dataset. Over half of these deaths are in individuals 75 or older and over three quarters are in individuals 65 or older. 3/14
The US is reporting over 2000 deaths per day from Dec 1 and I believe will do so consistently throughout December based on daily case loads above 120k starting early November. 1/4
A drop in reporting over Thanksgiving weekend has made for some difficulty in directly comparing 7-day averaged deaths, but the trend is clear. Red bars are daily reported deaths from @COVID19Tracking and black line is 7-day sliding average. 2/4
The simple projection of 1.7% of reported cases into deaths 22 days later has remained largely accurate, although drop of reporting during Thanksgiving weekend is quite clear. We'll know soon whether 7-day average returns back to projection. 3/4
The authors do a careful serological investigation, but it necessarily suffers from testing a large number of samples with an assay that is not perfectly specific. 2/10
The ELISA used by the authors has a stated specificity of 99.3% and the authors tested 519 "true negative" blood samples collected from 2016 to 2019 from healthy adults and suspected hanta virus patients and observed 3 false positives (0.6%) matching this specificity. 3/10
Another update on #COVID19 circulation in the US. With today's report we're seeing an average of ~172k daily cases reported compared to ~157k a week ago, and we're seeing ~1650 daily deaths reported compared to ~1200 a week ago. 1/10
Although this is still a staggering amount of cases and growing daily, the rate of growth at the US level appears to be (at least temporarily) slowing. Here, I've plotted data from @COVID19Tracking, showing daily cases in the US on a log scale alongside 7-day moving average. 2/10
Throughout October we saw steady exponential growth of the US epidemic (indicated by linear-on-a-log-scale dynamics and shown in the graph as the dashed straight line). Early November outpaced this steady growth but has recently slowed. 3/10
When I ran these simple lagged case fatality rate (CFR) calculations last week I was surprised and troubled at how big the predicted numbers of deaths in the coming weeks were. Since then #COVID19 daily case counts have continued to rise. 1/10
@alexismadrigal and @whet describe in much better detail the simple logic behind this calculation here: theatlantic.com/science/archiv… and they do a thorough job investigating assumptions of the method. 2/10
Ryan Tibshirani with the Carnegie Mellon Delphi Research Group very helpfully did an independent replication of the method here: htmlpreview.github.io/?https://githu…. 3/10
One small note about these trials. It's often assumed that vaccines are only a proxy for immune response to natural infection. However, there's nothing that prevents vaccines from inducing better, more durable protection than natural infection. 3/8