Daily Status, Sept. 4


Daily Status, Sept. 4:

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

Summary/Situational Awareness

Again, today's concern are with the universities.   Only W&M and GMU are doing well doing well (W&M), with no increase since the students arrived.  Meanwhile, there is community spread is present at Virginia Tech, UVA, JMU, Radford, and VCU. CNU and ODU just brought the students.  JMU is sending the students home, which could lead to other problems.   More on this in the section title "Colleges".  The discussion of colleges will take up most of the new discussion

Across the commonwealth, there were about 1111 reported new cases .  This is somewhat more than average number of cases in the last three week , but within 1 standard deviation.  Overall, cases are increasing at just over 1% per day. It is worth noting that 20% (210) of the cases are directly related to colleges.  Regionally, all parts of VA are increasing except NOVA and eastern VA. SW VA is leading the pack, largely the result of the outbreak at Radford and VT.  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, 20% of the cases are affiliated with a combination of Radford, JMU, VT, UVA, and VCU; those schools account for 1.5% of the population.

Note that in about 10 days, I expect an increase state wide as the students from JMU return home and infect their families, etc.  More on this in local section.


The statewide numbers are increasing slowly (about 1% per day; the growth is solely the result of the outbreaks at some colleges).  Outside of college environments, we are doing ok.  The best way to describe the situation is: Yesterday, the sky was not falling and today, we are not doing great.  But, as locations go, much of Virginia is improving, no overall region is particularly concerning (SW is explained by college outbreaks).  We are around the median for all states.

What is most noticeable is the worst part of the state per capita is SW VA, though NW VA is getting worse (JMU).  This is a dramatic change from the situation earlier.  SW is high mostly from the outbreak at Radford and now VT.  It is also with noting that Eastern VA's rate of improvement seems to have slowed.

The three week growth rates are (in fraction per day)

NOVA: 0.997 -- GMU

Central VA: 1.008 -- UVA & VCU

Hampton Roads/Eastern VA:  0.982 -- W&M & CNU

SW VA: 1.025 -- VT & Radford

NW VA:  1.023-- JMU


The state as a whole is is increasing at 1.011.

The following charts are for the 5 regions/trends.  It is worth noting that for NW and SW VA, the recent uptick are 100% the result of the case surges at VT, Radford & JMU. Note that the total number of cases is similar in all regions in spite of the population variations.  In fact, there are more cases in SWVA than NOVA or Hampton Roads.

Local/Northern VA:

The overall trend in Northern Virginia indicates, that after correcting for testing, the case load has dropped by more than a factor of 10x since our early may peak, though significantly higher than the early July minimum.  However, over the last several weeks, Northern VA has been essentially flat, at about 240 new confirmed cases a day, but over the last week, has started to increase again.  The current rate is  more than twice the rate from early July (120 / day), but down from about 3000 cases per day at the peak (because of the availability of testing, 40% of the tests were positive in northern VA, indicating that only 1 in 8 cases were confirmed).  Hospitalizations and deaths are also down from the peak, but up in the last month.

Right now, no jurisdiction is increasing by more than 1%.  But, Fairfax and NOVA is increasing.  A 1% increase (1.01 Rt) is doubling in 70 days.  

Fairfax Co.: 0.999
Arlington Co.: 0.967
City of Alexandria: 0.971
Prince William Co.: 0.997
Loudoun Co.: 1.014

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. 

I expect the numbers to increase locally (and statewide), as an unknown number of infected JMU students return home.  Some will infect their families, and possibly the broader community.  As an example, there are currently  about 77 cases in the greater Vienna area (population 64000).  James Madison HS sends on average 32 students per year to JMU, which means about 128 students.  If most of them come home, that will increase the number of cases.  If they spread the disease only to the immediate family, look for probably and extra 30 or so cases in 10-14 days.  

The weekly case numbers are nearly uniform in all jurisdictions, with the exception of Prince William. 

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, only Vienna and McLean have leveled off.  The less wealthy parts of the county continue a slow growth in cases. Arlington and Alexandria seem to have leveled off, which is positive.

Age Distribution: 

NOTE:  THIS CHART WAS NOT UPDATED.  I have a data processing error at the moment.

The age distribution of cases shows growth (RT>1) among all age groups, but the working age people (young adults & middle age) are higher than younger and older groups.  And once again, the Teens and Tweens are showing the slowest growth rate (practically flat).  Once again, the teen bubble's social isolation from anyone not a teen is working for them.  It proves if one only associate with non-infected individuals, then the risk is low.  However, based on observed behaviors among that age group, if the disease expands at all, then there will be a problem.  

One interesting aspect of the case numbers is a comparison of the rate of cases for teens (about 0.02% of all teens in the commonwealth) are reporting to be positive, but the numbers for returning students at colleges are more like 0.25%, suggesting that most of the teens are not being diagnosed, and probably means that only 10% of that age group are sick enough to justify testing.


Before I get into details, there is two recent hospitalizations in Harrisonburg.  That may or may not be affiliated with a JMU student.  

My advice for colleges in trouble are not to send the students home -- at least not without tests.  Most students will be fine; the home communities could be problematic.

I am now tracking ODU, and it has zero resolvable cass 


% Positive

VDH Cases*

Estimates Cases**

Dashboard Cases***

% of population infected ****

Va Tech





















































* VDH cases are based on the cases either in the zipcodes containing the student population or the community.  In addition, I remove the rate of cases prior to students arriving on campus
** 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.

Large Scale Community Spread:

RADFORD (linked to the university Dashboard)

First of all, they finally have a useful dashboard, but it is not updated daily.   Last night, I was thinking about Radford:  the trend is more linear than exponential in the numbers, but that is because they seem to only be able to test about 80 people per day, which limits the number of positives to 80/day.  It occurred to me the best way to understand the situation is by modeling.  Looking at the data, it appears the growth in reported cases started around 8/19; this suggests the cases started 10 days early (typically a 10 day lag from infection to confirmation).  For the first few days, the case rate grew at 60% per days, then saturated the testing.  If we assume it continued, and limit the numbers to the population size, we find that, in fact, Radford should be improving now, but not because of anything they did; rather, they have achieved herd immunity.  This is supposition based on modeling. Other data points that contradict this is prevalence testing by the New River Health District to help Radford asses the situation.  Of the people tested, only 5% were positive.  Modeling suggests that on last thurs and friday, the number should have been 20% or so, so that means either the modeling is overstating the growth (likely -- 60% is really high) or tested was not random (limited to only those feeling ok and not proved positive).  With that, assuming a 30-40% growth rate, we get about 5% late last week.  Today, it is much higher, but at the peak.  Herd immunity the hard way....  


JMU is going on line.  There is not much more to say.  If you have a student from JMU, try to get them tested prior to bringing them home, and it would be advisable to assume the student is infected.  Note there is one new hospitalization in Harrisonburg; I have no information if it is a student or a member of the broader community.
We have seen the prevalence of the virus in Blacksburg increase with the return of the students.  The school is over 1% of the student body 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 so far is manageable but it is at a tipping point.  They will be okay if they can limit the addition spread.  They continue to have significant space for quarantining on-campus students, but the off campus students are on their own. 


VCU is showing signs of community spread.   VCU's problem, though is the space for isolation is and quarantine is near capacity.  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.  

The students are just returning to UVA.  With the students return, there has been a marked increase in cases.  It appears there is community spread. And it is growing.  Between the increase in the percent positive and the absolute numbers increasing, UVA is trending in the wrong direction.  

 Watch List:

Other schools:

William & Mary -- so far so good -- No evidence of community spread (no cases with several thousand students on campus now.  Right now, W&M on campus is limited to Freshman, Transfers, RA's/OA's and on-campus grad students. (on campus for about 3 weeks).  In addition, there are some upperclassman who live off campus.  The rest will return in the next week or so.   It is worth noting that pre-arrival testing has identified 19 cases, which were not allowed on campus. 

CNU -- Just reopening; looks ok but the student have not been present long enough to see community spread.

UMW -- Not open yet.

GMU -- Nothing noteworthy.


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.    


One thing that is clear is the only schools that are not showing large scale community spread are those that tested all students prior to arrival at school.  Testing was critical, and it has to include the off campus students.  Without testing, asymptomatic and presymptomatic spread will infect the campus.  Spread of the disease requires 1) the disease to be present, and 2) the correct environment.  College is a good environment for the disease to spread -- tight quarters, roommates, etc.  Having no disease in the student population is a good way to start.  Long term, we will see what happens.  If I had to guess, the next to fall will be VT (near as I can tell Radford will stay open no matter how bad it gets).  After Tech, VCU then UVA.  GMU is doing a surprisingly good job.  W&M could make it to thanksgiving, but they have an increased challenge when the remaining student return this coming weekend.

FIRST:  DO NOT BRING COLLEGE STUDENTS HOME FROM THE IMPACTED UNIVERSITIES WITHOUT A COVID TEST UNLESS YOU ARE WILLING TO RISK EXPOSURE TO YOUR HOME FAMILY UNIT.  Statistics show the kids might feel sick, but will most likely need no significant medical intervention (99.5%). On the other had, about 10% of the parents will need significant medical intervention if sick.  
I want to talk a little bit about the difference between political decisions and science.  Ideally, politics is balancing the multiple facets of the problem to come up with an acceptable solution.  For example, balancing the risk of the pandemic to the cost of a shut down.  Science can advise, but I -- as a scientist -- am focused on what I know, which is the data and the models.  The actions based on that data and model analysis are political decisions.

I am writing this before I have seen Sunday morning's data (actually, writing this Saturday Afternoon).  However, my expectations are the outbreaks at Radford and JMU will appear to be worse (it is possible that Radford has peaked but because of the delays in reporting, it is not clear yet).  JMU could still stop the outbreak.  What they do in response to the outbreak is a different decision.  The political decision will need to look at information I do not have: the capacity of the health system, the impact to the broader community, etc.  There will be negative consequences on society if they just shut down:  sending the sick and contagious home will spread the virus to other locations.  The reality is, of the total number of students at JMU and Radford, the total death toll from the virus will probably be in the low single digits or so -- worst case if everyone gets sick.  And maybe 20-200 will be hospitalized -- and this could be high.  

The problem is, if you send the kids home, they will bring the virus with them.  The parents are in a more vulnerable population.  50 something have a 1-2 % mortality on average, and potentially much higher with comorbidities.  For example, if my offspring were to bring the virus home, I would have to isolate myself -- I have several comorbitities.  

Furthermore, at the universities, many of the staff -- either professors or support staff will similarly have comorbitities.  That is the political balancing act.  

The same decision the public schools had to make.  The kids are not the problem.  The parents, teachers, custodians, and society as a whole are what factor into the decision.
It is not just the science of one field.  It is the science of the disease balanced by the social science/implications balanced by the economics.


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

State Actions: Impact on Growth:  TBD

Figure Descriptions:  TBD

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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