COVID-19 Status for VA: Sept. 9

Daily Status, Sept. 9

Reminder:  any sections that are unchanged since yesterday are grayed out.

I wrote a supplementary blog describing how I monitor colleges from zipcodes.

Summary/Situational Awareness

It looks like some colleges are either getting a handle on the virus or achieved herd immunity, or we are still seeing effects of the holiday weekend.  But, Radford and VCU are stable now.  

Across the commonwealth of Virginia, there were 882 reported new cases of COVID-19.  The number lower than the recent trends, but by significantly less than one standard deviation from the mean.   Overall, cases are essentially flat for the last three weeks. It is worth noting that, over the past three weeks, 14% of the positives have been from colleges; today,  colleges account for 18% (161) of the cases are directly related to college; without the college cases, the numbers would be decreasing by 1%/day Regionally, only  NW VA is increasing, largely the result of the outbreak at Radford, VT, and JMU.  The testing numbers across the state remain ok, but not great, at around 7% positive.  I would like to see the overall positive rate under 5%

Outside of college towns and a few smaller cities/towns, the state is doing well. In fact over the last three weeks, 14% of the probable active COVID cases are affiliated with a the colleges of Radford, JMU, VT, UVA, and VCU; those colleges account for 1.5% of the population.


Over the last several weeks, we have seen a trend where the more rural parts of the state, with a few isolated large colleges have been trending poorly compared the more urban setting (even if those with colleges).  For example, Hampton Roads and NOVA have not seen impacts with the colleges reopening whereas SW & NW are being swamped.  In particular, the New River area is showing 0.8% of the population positive in the last 10 days or so.  This is the result of the annual migration of college students to Blacksburg and Radford.  

Regional growth rates are (in fraction per day) are primarily impacted by anomalously low case numbers the last two days, probably the result of the holiday.

NOVA: .990 -- GMU

Central VA: .997 -- UVA & VCU

Hampton Roads/Eastern VA:  .962-- W&M, CNU & ODU

SW VA: .994 -- VT & Radford

NW VA:  1.017-- JMU


The state as a whole is is increasing at 1.002.

Daily case count per 100,000 is a often sited metric (below 10 (0.01%) statewide would take VA off the quarantine list .  The following table shows the number per region. 

Daily Cases/100,000 
(corrected for testing)


Last month

Last week
















The following charts are for the 5 regions/trends.  Again, SW VA, even with the lower population, has more cases than any other region.  Note the nosedives we are seeing are probably a processing artifact of the low case numbers for the holiday; I expect the trends to revert to where we were prior to the weekend by Thurs.

Local/Northern VA:

The last several days in Northern VA have seen significantly lower case numbers several days of 1-2 standard deviations below our mean.   I suspect this is largely a result of less testing over the holiday weekend.  If the trend continues for 1-2 more days, it will be good news. 
Currently, every Northern Virginia jurisdiction is showing a decrease.  This may bay be an artifact of the low numbers for the last several days (Holiday weekend).  

Fairfax Co.: 0.989
Arlington Co.: 0.970
City of Alexandria: 0.991
Prince William Co.: 0.989
Loudoun Co.: 0.990

The growth rate is defined as Rt, or the growth time constant.  Simply, todays number are approximately the growth rate times yesterday's numbers.  This is the exponential time constant.  Fortunately, the time constants are about 1, and our rate of cases is about 7/100,000 per day.  Ideally, we would be 0, but 7 is much better than our peak in which was around 30/100000K. 

About 14 day ago, Arlington began enforcing social distancing guidelines. Since then, there trend has gone from 1% per day to -5% per day.  Now, Arlington is doing the best; Alexandria and PW are doing worse.

What is most noteworthy of the NOVA Zip code map is the the overall lack of contrast:  the bad areas are doing better, and the good areas are doing worse, with the exception of two areas near the fringe of "Northern VA".  (The state would call those NW VA). 
In Fairfax County, the cases are about static over the last few weeks.  By comparison, Arlington and Alexandria are showing significant declines since Arlington started enforcing social distancing in late August. By contrast, Vienna and Mclean, while still very good, have shown an increase.


Last month

Last week

Fairfax Co







 So. Alexandria






 Annadale/Fall Church







 No. Arlington



 So. Arlington



 Alexandria City



Note that the current ups trend in Vienna may be a random blip, or it may be concerning; similar patty were observed in early July and early August.  Early in the month is probably a coincidence.  It is also possible that some college students listed the home address with off-campus covid tests.  Time will tell.

Age Distribution: 

The trends/growth for the the middle aged gas dropped to be similar to the teen/tween and elderly. If we look at state-wide numbers, we see a very different trend set:  all ages are doing well except those that include college ages (18-24).  As we can see, NOVA flollows the growth trend of the state, except for teens/tweens.  I am confident that growth is driven by students at college.

             <10    0-19.  20-39.  39-59.  60+
  NOVA  0.99    1.01    0.99      0.98   0.98
  AllVA   0.98    1.03    1.00      0.99   0.99

Unfortunately, I can not parse out 18-24 separate from the other groups.


Before I get into details, there are at least three COVID hospitalizations in colleges that are from ages consistent with college students.  2 at JMU, one at VT.  There could be more, if upon admission, the student gave the home address.

Note that the reported numbers were low at all colleges yesterday.  I suspect this was related to the reporting being in the middle of the long weekend.  I am not changing anything other than the tables and charts based on today's numbers.

My process combines the VA Department of Health data and what is reported by the colleges.  The report is as of 11:00 AM ET.

RED means there is clear evidence for community spread
YELLOW means there may be community spread; still ambigious
GREEN means no evidence of community spread
BLACK means they went online.


% Positive

VDH Cases*

Estimates Cases**

Dashboard Cases

% of population infected ***

Va Tech




























































** estimated number of cases is an attempt to normalize for testing limitations. Specifically, I assume at 5% positive, 100% of the cases would be caught. so I normalize it to that value.  If the % positive is very high (>40%) I am likely overestimating the numbers.
*** Dashboard cases are only counted if I can find the dashboard.  In some cases, it is difficult to distinguish positive tests from cases (1 case may have multiple positive tests; that is mostly at VT).  I include active cases if reported, otherwise, I use total cases.
****% population uses the total reported number of students rather than just those on campus; it may be off when the percent positive is above >40%.
***** Old data, not updated for today.
****** Active cases, not total cases

Large Scale Community Spread:

RADFORD (linked to the university Dashboard)

The numbers of new cases at Radford seems to have peaked.  We do not know how many people have/had the disease.  Because the percent positive remains as high as it is, though, most of the people who need to be tested might not be able to be tests (or at least might not have been able to get tested in the last several weeks).   At this point, my only recommendation is to perform serology/antibody studies to retrospectively determine the number of cases.   Radford tested the students prior to arrival, but allowed students on campus prior to the test results.


JMU is going online.  JMU has been fairly transparent with the situation, but could not get ahead of it.  At this point, it is mitigation. They sent the healthy students home, and are allowing the positive to stay on campus, which is critical for society as a whole   There are now two hospitalizations in Harrisonburg that are of the age group expected for College students.  JMU did not require testing prior to arrival on campus.
We have seen the prevalence of the virus in Blacksburg increase with the return of the students. The most concerning aspect of Va Tech is 20% of the tests are coming back positive.  That suggests that either they are rationing tests, or they are undercounting.  Either way, I estimate indicate more than 5% of the student body is positive. VT will start updating the dashboard each day next week.   The school has a plan, but is not clear how much impact the plan is having on off campus students.  The rate of infection may be at tipping point. VT claims there is no uncontrolled community spread, but the data does not support that assertion. Virginia Tech tested only on-campus students.  
The With the students return, there has been a marked increase in cases.  It appears there is community spread. And it is growing, but relatively slowly.  large scale community spread, if it occurred, should show up in the next several days  Between the increase in the percent positive and the absolute numbers increasing, UVA is trending in the wrong direction.  UVA tested all students prior to arrival on campus.

Watch List:


VCU seems to have the virus under control -- it was promoted from RED to YELLOW.  The numbers have shown no significant increase in the last several days; quarantine and isolation space is becoming more prevalent.   Being in an urban setting the zip-code and regional surveillance that works well at some of the other schools is not particularly helpful here.  So, I have to rely on the dashboard.   

Other schools:

William & Mary -- so far so good -- No evidence of community spread.  There are now cases on campus (I think).  I am assuming they have somewhere between 1 and 9 cases; looking at the numbers for Williamsburg, it is probably 1 or 2.  It is worth noting that pre-arrival testing has identified 20 cases, which were not allowed on campus. W&M will retest all students next week. W&M tested all students prior to arrival in town. 

CNU -- Students have been back upto 1 month. A few cases.  Under control.

ODU -- Nothing noteworth.  My concern with ODU is they did not test the students, so there may be asyptomatic/presymtomatic spreaders on campus (see JMU).  There dashboard is a week old, which would be concerning, but the data suggests there can not be more than a few cases a day.

UMW -- Not open yet.

GMU -- Nothing noteworthy.  GMU tested all students.


Based on the above charts, the issue is no longer the communities.  The issue is the campuses.  We are seeing the growth in New River (VT/Radford) and Harrisonburg.  The sad thing is those communities had the lowest numbers prior to the students return.    


Masks are our friends.  Masks significantly reduce the risk of disease transmission, if they are worn correctly.  The purpose of masks are 1) to contain any virus you may discharge through breathing, talking, coughing or sneezing, and 2) to protect you from incoming viruses with your breathing.  In order for the mask to function, it must cover the mouth and nostrils.  The chin and neck do not need protection (unless you have a tracheotomy).  I am seeing too many people with the nose and/or mouth exposed.  And I have even seen town employees with the masks that way.  Confronting does not seem to work, except sometimes with a neck mask, people just forgot to put it on.   It is not enough to have a mask; it most be worn properly.  WHO put the following graphic:

I try to keep my political biases out of it.  Unfortunately, some politicians have turned data into a political issue.  Yesterday, while driving home, I heard a prominent politician state that the America's numbers would be much better if we excluded NY.  I am not sure when the quote was captured.  But, I am a data and science person; based on that, I wonder how policy can follow when data is fabricated.  The data for cases in the USA, with and without NY are shown below. In April, our cases there about 50% NY, since then NY has been doing better.  Since June 1, NY has accounted for 1.5% of the cases nationally, even though it has 5.8% of the population.  So, currently, NY is outperforming the country.  Even including the early days, NY is at 7.2% the cumulative cases, about 25% higher than you would expect.  By comparison, Florida accounts for 10.2% of the cases but 6.3% of the population.  And FL should have known better.  (VA is at 2% of all cases, and 2.5% of the population).

The numbers do not lie.


1) You can repost / share in the entirety by forwarding the link, 2) If you want share partial content, you must receive my permission – I need to make sure you understand what I am saying. If anyone sees this work being used without attribution, please let me know as soon as possible. I am willing to have an informed discussion / debate on my approach, but I want to make sure the proper context is captured.


Source data is from the Virginia Dept of Health COVID Site

Why I did this:  About the blog

Other Sites:  John's Hopkins

Kids can pass covid to parents: Pediatric SARS-CoV-2: Clinical Presentation, Infectivity, and Immune Responses

A fun video showing masks work, guy style:


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