Hi James,
>> Let's peg vaxxed immunity at 90%.
Please don't! This was true (a) against original virus, (b) immediately after vaccination. It's lower against Delta, and it's waning over time. Financial Times visualization of latest evidence:
So, even 80% is optimistic. 90% is wishful thinking. Note: infected people can still transmit to others, which is what we're concerned about here.
>> let's think about the 100% vaxxed scenario
So you now agree we should mandate vaccination?
>> 900 never even know it
Not quite. You might be thinking "exposed" where I said "infected" - big difference. My 1000 number is based on real-world examples where an infection cluster of that size developed quickly, before anyone noticed. If there is more vaccination, then fewer
exposed people will get infected, so a 1000-people cluster becomes much less likely. But that's exactly why Delta is so bad. For each infected person, 5-8 more get exposed, a number that was only about 2.5 for the original 2019 strain.
Some math for the (absolutely best-case) scenario of R0=5, 100% vax rate, 80% immunity: Rt = 5*[1-100%*80%] = 1.
Precisely! So we finally got you on board that the mask mandate at least for students was a good idea? That's awesome!
Yes events of this kind are indeed rare if we accept that they are possible and take steps to prevent them. I'm very happy to see that you seem to have come around on the desirability of doing so. 😊
Lucas
Sent: September 3, 2021 12:31
To: Lucas Herrenbrueck
Subject: Re: Estimate of % students vaccinated. Message from the President: Return to Campus planning updates
Well Lucas I only asked a question about inference from the President's stats. But let's think about the 100% vaxxed scenario using your numbers and proportions. Let's peg vaxxed immunity at 90%. And let's further assume that immunity = asymptomaticity (an oversimplification, but perhaps a useful one).
Under those conditions, your 1000 fully vaxxed people get infected. 900 never even know it. 80 have to isolate. 15 get one or more of the ill-defined conditions--ranging from headaches to etc.-- grouped under "Long Covid". 2-5 are hospitalized. None dies.
Moreover, considering percentages of continued masking, social distancing, plus ventilation, etc, it would seem that we can expect even events of this kind to be quite rare (though this is difficult to quantify).
Considering the narrow horizon of instructor-student contact -- a couple of hours a week, for the most part in large, well-ventilated rooms at considerable distance -- I would say precipitation of such events along that vector seems very unlikely.
So yes, as far as teaching without a mask goes, I would say that's "living with Covid." JDF
Sent: September 3, 2021 11:41 AM
To: Igor Herbut; Bernard Crespi; James Fleming
Cc: academic-discussion@sfu.ca
Subject: Re: Estimate of % students vaccinated. Message from the President: Return to Campus planning updates
Hi everyone,
James: I wonder if you are aware of the evidence that Delta can spread, quite easily,
even in a 75% vaccinated
population?
Igor: thanks for the calculation! I concur with it, but also want to remind that we'll have incoming international students who won't be all vaccinated, at least not until November.
But let's be positive and say 75% are fully vaccinated for the next few months - incidentally, that's exactly what we assumed in our
August 4 Open Letter. Delta says that's not enough, not nearly. Basic epidemiology: the disease the spreads until R0*[1-{fraction immune}*{efficacy of immunity}] < 1.
Based on the current state of the science, R0=5-8 and vaccine efficacy against infection is 50-80% (depending on which vaccine and how long ago it was taken). Let's be optimistic again and set R0=6 and VE=.8. This means Rt = 6*[1-75%*80%] = 2.4, which is identical to the original strain from 2019!
So without additional measures like masking, distancing, rapid testing and effective contact tracing, outbreaks would spread just as quickly as in January-March 2020.
Now, given high vaccine efficacy against serious illness and death, this is not an "everyone dies" kind of situation. But it easy to see how a single superspreading event - let's say a pre-symptomatic instructor who made the personal choice not to wear a mask, or a sneezy student who didn't want to miss a midterm - could result in 1000 follow up cases, out of which:
- 800 will 'only' have to isolate for 2 weeks
- 150 will 'only' develop a currently untreatable chronic condition which causes severe headaches, fatigue, and loss of brain function
- 20-50 will be hospitalized
- 1-5 will die.
These numbers are guesses, but they're consistent with current data on likely Covid outcomes in a youthful and highly vaccinated population. If there is spread to unvaccinated children and elderly relatives, we would expect worse.
If we get to 100% vaccinated on campus, then the numbers above become less dire - maybe cut them all in half. (Given Delta's high R0 and breakthrough rate, even 100% vaccination does not confer mathematical herd immunity.)
Just to be clear, is this what we mean when we say "we need to learn to live with Covid"?
Lucas
Sent: September 2, 2021 6:13:39 PM
To: Bernard Crespi; James Fleming
Cc: academic-discussion@sfu.ca
Subject: Re: Estimate of % students vaccinated. Message from the President: Return to Campus planning updates
Bernard,
We do have some idea: according to the last bc cdc report at
http://www.bccdc.ca/health-info/diseases-conditions/covid-19/data#Situationreport
which ends with the week August 13 - August 21, in the age cohort 20-29 80 % (65%) were partially (fully) vaccinated. I would guess that the SFU students are more likely to be vaccinated than the general BC population of the same age. Adding twelve more
days that passed since August 21st during which the percentages could only increase would suggest that the conservative lower bound on the percentage of fully vaccinated SFU students is around 70%.
Cheers,
Igor Herbut (physics)
Sent: Thursday, September 2, 2021 5:01 PM
To: James Fleming
Cc: academic-discussion@sfu.ca
Subject: Estimate of % students vaccinated. Message from the President: Return to Campus planning updates
James
It is likely that the unvaccinated are over-represented among those who did not respond to the poll,
which is about half of students (there was a 53% response rate).
We thus have basically no idea what % of students are fully vaccinated except to say that it is probably between ~50% and 90%.
If we had an 80 or 90% response rate, we would have a much better estimate.
Thanks for listening,
Bernie Crespi, BISC
Preliminary results from the vaccination status survey launched on August 27 are very promising. Among respondents:
- 96.4% of faculty and staff and 90.1% of students are fully vaccinated
- 98% of faculty and staff and 95.2% of students are partially vaccinated
- 1.1% of faculty and staff and 1.8% of students cannot or are choosing not to be vaccinated
- To date, 67% of faculty and staff and 53% of students have completed the survey. The survey remains open and I encourage you to participate using the link provided in your inbox if you have not already.
Sent: September 2, 2021 4:45 PM
To: Cynthia Patton; SFU Administration; academic-discussion@sfu.ca
Subject: Re: Message from the President: Return to Campus planning updates
Sent: September 2, 2021 4:00:41 PM
To: SFU Administration; academic-discussion@sfu.ca
Subject: Re: Message from the President: Return to Campus planning updates
Dear President Johnson:
I simultaneously received Bulletin's from SFU and UBC. Can you please explain why UBC is implementing Mandatory Testing, with an exemption for the vaccinated, but SFU is only suggesting it might use testing if vaccination status is undeclared or non-complete (and how does one prove this?)?
I quote from President Ono's annoucement of this afternoon:
|
"UBC recently announced a decision to require COVID-19 rapid testing for all students, faculty and staff, with exemptions provided for those who are fully vaccinated against COVID-19. We would now like to provide an update. COVID-19 rapid testing for all students, faculty, and staff UBC will require COVID-19 testing for all students, faculty and staff, with exemptions provided for those who are fully vaccinated against COVID-19. A process for confidential self-disclosure of vaccination status will be implemented next week, with details provided at that time. Once the program is live, you will be asked to go online and use your Campus Wide Login (CWL) to complete the following steps.
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Sent: September 2, 2021 2:15:39 PM
To: Cynthia Patton
Subject: Message from the President: Return to Campus planning updates
This message is sent on behalf of Joy Johnson, president and vice-chancellor. It has been sent to all faculty and staff.
As we approach the beginning of the fall term, we continue to prepare our campuses for the return of students, faculty and staff. It has been heartening to see groups of students taking campus tours this past week. Our return to campus plan for the fall includes layers of protection to help keep our students, faculty, staff and visitors safe, including additional safety measures in response to the recent rise of cases in BC. We continue to work with public health to follow their guidance on mandatory masks, declaration of vaccination status, pop-up vaccination clinics and rapid screening on campus.
We will be providing updates regularly with as much information as we have. Please keep in mind that more detail will come and that we will continue to refine protocols and respond as needed.
Vaccination is the best defense
Preliminary results from the vaccination status survey launched on August 27 are very promising. Among respondents:
- 96.4% of faculty and staff and 90.1% of students are fully vaccinated
- 98% of faculty and staff and 95.2% of students are partially vaccinated
- 1.1% of faculty and staff and 1.8% of students cannot or are choosing not to be vaccinated
To date, 67% of faculty and staff and 53% of students have completed the survey. The survey remains open and I encourage you to participate using the link provided in your inbox if you have not already.
Response to our on-campus vaccination clinics has been positive, and I am heartened to see members of our community taking this important step. More clinics are scheduled and I encourage those who are not yet fully vaccinated to make a plan to do so. This is the most important thing you can do for your own safety and the safety of those around you. Proof of vaccination will also be required for access to non-essential activities at SFU as we apply the BC Vaccine Card in accordance with public health.
Masks are mandatory in all indoor common spaces
You are required to wear a mask in all indoor common and learning spaces, including classrooms. Come to campus prepared with a non-medical mask. Disposable masks are also available from Student Central in Burnaby and at the information desks in Vancouver and Surrey.
A very small number of individuals may have an approved exemption from wearing a mask.
It is important to remember that some individuals cannot wear a mask for valid medical reasons. Be kind and reserve judgement. There are processes in place to oversee mask compliance in learning spaces, including what instructors can do in the case of a student who is not properly wearing a mask in a classroom. These processes have been provided to instructors. Individuals should not confront or challenge others regarding masks. Any questions about safety or compliance should be submitted using the COVID-19 safety reporting form.
Declaring your vaccination status
Next week we will launch a third-party website to gather vaccination status data of our campus community. The website will be accessible from your smartphone or desktop. The process is confidential, the data is secure and SFU will not have a record of your personal information. All members of the SFU community, including, faculty, staff, students and those who plan to visit one of our campuses are required to register and make a self-declaration.
The site will ask you to enter your vaccination status. If you are fully vaccinated, that is the only step required. If you are not fully vaccinated, you will receive information on how to schedule a vaccination and get rapid screening. The website also allows for symptom screening, and we will encourage members of the SFU community to use the site to regularly self-monitor.
We are working with public health to renew our on-campus rapid screening pilot. As we determine next steps, we will refer those who need testing to local testing centres. This element of our planning is underway and we will provide more information as we have it.
Everyone is going at their own pace
Some will return to campus next week energized and excited; others will be managing many details in their personal lives; and some will be struggling with the current reality and the impact of the past 20 months. Be patient with one another. Look for ways to support one another and extend compassion. You never know what someone else is dealing with, and how much kindness can help.
If you need support, don’t hesitate, reach out. Resources for mental health and well-being are available.
More information
Visit the Return to Campus website, which is being updated this week with the latest information. Have questions about our return to campus? Email covid19@sfu.ca.
Sincerely,
Joy Johnson
Pronouns: she, her, hers
President and Vice-Chancellor
Simon Fraser University