Abstract
No residential college or university operating in-person in the US is doing as much testing as they should and only about 20 are likely to be able to manage outbreaks this fall. Commuter schools may be fine. Testing everyone every 2 days is best but no school is doing that because tests are too scarce and expensive, and it takes too long to get test results. The two types of interesting schools to watch are military academies (some testing, lots of behavior modification and policing) and a handful of schools with in-house capability or special deals (mainly with the Broad Institute). Sufficiently cheap tests may be abundant in a few months. In the meantime, given the scarcity of tests, higher ed should only be using tests as part of efforts to make testing cheaper and faster for everyone.
Higher ed is not doing enough testing to safely reopen
Whether higher ed is doing enough testing is not an interesting scientific question: scientists know that few, if any, higher ed institutions are doing enough testing to prevent outbreaks. Part of the problem is the CDC, which discourages surveillance testing in its guidelines for reopening higher ed institutions, presumably for political reasons.
Covid-19 is hard to manage because of 2 A’s: asymptomatic and aerosol. Many people with Covid-19 are asymptomatic—they don’t show symptoms of disease—but can spread Covid-19, anyway; thus, you need a test to know if someone is contagious. Covid-19 spreads as an aerosol. When you exhale, your lungs release small particles of water and the small particles, aerosols, can hang in the air and spread around. Aerosol spread means that Covid-19 can be transmitted even if people stay 6 ft apart and wear masks. Distancing and masks help enough that we should maintain these practices but they are not so powerful that it’s easy to figure out everyone who a patient could have infected. Therefore, to manage Covid-19 outbreaks, surveillance testing is needed: frequent testing to find people who are infected and don’t know it.
This paper is the big one people point to saying that colleges need to test everyone every 2 days. It’s a modeling study. The authors really say that anything from weekly to daily might be right, depending on how well everyone follows the rules. In principle, if you could keep everyone locked up outside of class and everyone wore masks outside of their dorm rooms, a campus might be fine without any testing; that would require extreme modification of college student behavior. Realistically, testing every 2 days is needed unless an institution can figure out how to get college students this year to act quite differently from any previous class.
Just based on how Covid incubation works, testing every 2 days makes sense because it should catch new infections after they’re detectable but before they’re contagious.
No college or university is testing every 2 days.
You can’t test everyone in a college every 2 days. The normal tests you’ve heard of are PCR tests on NP (nasopharyngeal) swabs. Turnaround time is too long (>2 days) and it is very expensive to buy faster turnaround time. The machines and supplies needed for these tests are scarce. Even assuming normal tests did have good turnaround time, at about $80 each, 1 semester of testing for 1 person is $4,000.
Fast and cheap tests are in development and if we’re very lucky, they’ll be here by the spring semester. Antigen tests are the main contender in this category; some exist but are not yet sufficiently abundant for frequent surveillance testing. This article describes a lot of testing advances in development. We’re not there yet.
About 20 schools might be able to make an in-person fall semester safe
Two interesting sets of institutions to watch are the ones testing twice a week and the military academies.
The military academies are not actually doing a ton of testing but at least they’re doing some surveillance testing, i.e., testing everyone regularly, not just people with symptoms or people who were in contact with positives or presumed positives. The military academies are making up for not testing everyone frequently by being military academies: they know how to teach people to follow orders!
Because testing is so constrained and expensive, colleges need their own labs or special deals to be able to do frequent surveillance tests, which you need if you aren’t dealing with students who are not cadets or middies. A list of institutions doing testing at least twice weekly is below. It’s not a long list. Most schools on the list are getting testing through the Broad Institute, which has a special relationship with Harvard and MIT.
One interesting example is Colby College, a small, liberal-arts college that bet big on testing early on this summer. Colby’s getting their tests through Broad for about $30 each, or $1,500 for a semester. They’re spending $10M this year on health and safety for 2,000 students.
Another interesting example is the University of Illinois Urbana-Champaign, which, last week, did 1% of the total amount of Covid testing that has been done in the United States. They’re using an in-house developed test. The test uses PCR but it uses saliva, rather than NP swabs. Fewer supplies and special chemicals are needed for saliva based tests, compared with NP tests. The materials for these tests cost about $10. Even so, they still require PCR machines, which are scarce.
The other schools doing twice-weekly testing are mostly using Broad or in-house labs.
Schools testing twice-weekly:
- Harvard University
- Amherst College
- Bates College
- Boston University
- Bowdoin College
- Brandeis University
- Clark University
- Cleveland State University
- Colby College
- Franklin W. Olin College of Engineering
- Massachusetts Institute of Technology
- Mount Holyoke
- Roger Williams University
- Simmons University
- University of Illinois at Urbana-Champaign
- University of New Hampshire
- University of South Florida
- University of Wisconsin at Madison
- Wesleyan University
- Yale University
This list was pulled from this Google Sheet
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