Credit: Courtesy University of Minnesota

As the school year concluded in June, optimism reigned. Minnesotans over the age of 12 finally had abundant opportunities to get the long-awaited COVID-19 vaccine. The state’s coronavirus positivity rate declined below 1 percent for the first time since the start of the pandemic. And parents, kids, and teachers looked forward to fall, and what they hoped would finally be a more normal school year.

But since then, the Delta variant has spoiled those hopes. New cases in the state now average about 1,500 per day, more than a tenfold increase since late June. Positivity rates have ticked up above the 5 percent that public health experts consider worrying. And that data doesn’t yet include possible increases from the Minnesota State Fair or the start of the school year (with the exception of Albert Lea, where the school year opened last week with a COVID-19 outbreak).

And the risk calculus has changed. In the early stages of the pandemic, young children seemed to contract COVID-19 less frequently than adults. When they did get sick, their cases were usually milder. But now, children are more frequently falling ill with COVID-19. Though children remain unlikely to become seriously ill with the virus, COVID-19 pediatric hospitalizations nationally reached their highest levels yet in recent days. And children under 12 still aren’t eligible for vaccines.

Scientists aren’t yet sure whether the variant has a more severe impact on children. But it is clear that this particularly contagious variant is spreading to children more quickly. And so the picture for returning to school looks very different at the start of September than it did in the halcyon days of June. The unwelcome shift back to uncertainty and fear has left parents—especially of kids too young to be vaccinated—with a familiar sense of dread, and a lot of unanswered questions.

So Sahan Journal called epidemiologist Dr. Michael Osterholm, the director of the Center for Infectious Disease Research and Policy at the University of Minnesota. Osterholm served on President-elect Joe Biden’s Transition COVID-19 Advisory Board, worked as state epidemiologist for 15 years, and co-authored the New York Times bestselling book Deadliest Enemy: Our War Against Killer Germs, in 2017.  

In a recent podcast episode, Dr. Osterholm outlined his concerns that CDC guidance for opening schools is outdated, and fails to account for the extremely contagious Delta variant. The CDC updated guidance August 4 to recommend universal indoor masking and testing for vaccinated people within three to five days of a known COVID-19 exposure (that is, if they know they were near someone who tested positive). But other guidelines remain unchanged. 

“The CDC recommendations, frankly, there are some valid and good points in them, but they’re built on a house of cards,” Osterholm said.

We asked him how schools, parents, and kids should be preparing for the beginning of the school year. How should the Delta variant shape how we’re thinking about back-to-school? His answer was bracing. 

“Well, it is a game changer,” Osterholm said. “And frankly, all the data that was collected before Delta was part of the variant challenge almost is not helpful in understanding what the risks are in schools and what we can do to redress those risks.” 

This conversation has been lightly edited for length and clarity.

‘The risk is very real’

On August 26, the American Academy of Pediatrics reported a five-fold increase in COVID-19 cases among children over the past month. Both nationally and in Minnesota, about 1 percent of children who tested positive for COVID-19 have been hospitalized. As cases in children rise, so have pediatric hospitalizations. Though a small percentage of kids have symptoms that last longer than four weeks, long-term complications can be serious. Meanwhile, a surge in other respiratory illnesses is straining pediatric hospital capacity in Minnesota.

Sahan Journal: What do we know now about the short-term and long-term risks to kids with the Delta variant?

Osterholm: Well, I think the risk is very real. I think we all want to get kids back to school. All of us. I mean, as a grandfather of five kids under age 11, I understand completely the need to get kids back. But we can’t put their safety at risk because we have an intense desire to get kids back to in-class learning. 

To justify it, I think people will use information from studies that were done before Delta appeared. And back then, I was one of those people that said we can likely hold school relatively safely. Not completely safe, relatively safely. But now look what’s happened. And so that’s all changed.

‘This idea of 3 feet apart is nonsense, scientifically’

While public debate and media coverage have often focused on masks in schools, they are just one of the tools schools can use to limit the spread of COVID-19. On his podcast, Osterholm describes a “hierarchy of environmental controls”—that is, an ordered list of priorities for limiting COVID-19 transmission in schools.

Sahan Journal: On the podcast you described a hierarchy of environmental controls for schools. Could you briefly outline that?

Osterholm: Where you can vaccinate individuals 12 years of age and older, that should be job one. That’s really important in the context of protecting children and teachers and staff in the classroom. You have to one, first of all, get teachers, staff and support people, such as bus drivers, vaccinated. 

Second of all, in the environment itself, the most important thing you can do to protect children is increase the ventilation. Each room should have at least five to six air exchanges an hour. There has to be no dead spaces in the room—areas that ventilation doesn’t pick up and exhaust out and put new air in. 

Then you need to look at how you help basically scrub the virus out of the air. We know that having air cleaners made with HEPA filters in a room can be very helpful. And if you can’t get one of those, can’t afford them, there’s a thing called a Corsi box, named after professor Richard Corsi. Simply take a regular box fan and buy MERV 13 filters from any hardware store and basically build one. It’s like a MacGyver activity, but you can do that. 

YouTube video

And then of course you have to reduce the concentration of people in a room. This idea of 3 feet apart is nonsense, scientifically. Nonsense. Think of smoking as an aerosol. If you can smell cigarette smoke from someone, then you could also be inhaling their breath with infectious virus. Could you imagine anybody being 3 feet apart from somebody and not smelling cigarette smoke? I mean, just see how illogical that whole approach is. 

So, the fewer people you have in a room, the lighter the load of virus will be if it’s in the room—meaning the number of people who are breathing potential virus into the room as well as the number of people that can get infected. 

And then, of course, masking comes in. This has been where I find it has been very frustrating, because what people have done is divide into two camps, mask or not mask, and that is not the question. The question is, how do you provide quality masking? You need to look at the kind of masks that kids are using, or the teachers, and so forth. 

I’m strongly supportive of masking, but we know face-cloth coverings provide very limited protection relative to what N95s or KN95s can do. That’s what we have to really look at. 

‘Testing students multiple times a week’

Though N95 and KN95 masks were often hard to find early in the pandemic, Osterholm said, they are widely available now. (Note, though, that N95 masks vary: While all will protect you from COVID-19, non-medical masks with valves may not protect others.) If you can’t find those, look for one approved by ASTM International, a standards organization that has developed standards for barrier face coverings. The CDC list of ASTM-compliant masks is available here.

Testing is another important part. If you can be testing students multiple times a week, you have a much greater chance to find it in their earliest stages of infection. The same thing is true of teachers and staff. That will help then assure that they are out of that environment as quickly as possible so they don’t transmit to more people. 

Finally, last but not least, families that have older kids, or the adults—they should be vaccinated. We see so many instances where the transmission to a child who then brings it to a school was actually from mom and dad or older siblings who could be vaccinated.  

If you cover all those, that’s how we’re going to approach school as safely as possible, not totally safe. Then if we do see transmission in school, and we can’t stop it in those first days, schools are going to have to look at distance learning. If for no other reason, look how many students will be in quarantine. 

‘Plexiglass is hygiene theater’

Sahan Journal: How do you see Minnesota schools acting on this hierarchy of environmental controls?

Osterholm: It’s varied. Some schools, the buildings are much more amenable to being able to do that. In others, ventilation systems are older and outdated, and it’s more of a challenge. 

If you can’t get as good of ventilation, that should be your high priority. That’s where you want to look at the air scrubbers as much as possible so that you’re taking virus out of the air. Do not buy all of these other kinds of devices that put things into the air. Okay? Those are pixie dust approaches to trying to reduce virus in the classroom. It’s really the HEPA filter kind of approach or the Corsi box approach. You want to filter it out with these very highly efficient filters. 

The other thing is, plexiglass is hygiene theater. People think that it’s effective, but it’s not. I think we wasted lots of money, time and effort putting all this plexiglass in place. Aerosols go right around it. If you and I were on the other side of a plexiglass screen that was 2 to 3 feet high and I was smoking on the other side, you think you’d smell it? You bet you would.

A plexiglass screen for classroom use at Minneapolis’ Pillsbury Elementary School, February 2021. Credit: Jaida Grey Eagle | Sahan Journal

Sahan Journal: What kind of financial investment do schools need to make these upgrades? 

Osterholm: There are funds available through the CDC and through the states to actually help support that kind of work. But it is going to be a challenge. Just something as simple as testing: The cost of testing is not insignificant. But you want to keep schools open or not? I mean, this entire portfolio of things needs to be brought to the table. 

That’s why I get frustrated when it always boils down to a mask or non-mask. That is such an unfortunate discussion. Yes, mask. Quality masks. But look at all the other things you can do, too. And we’re missing that in schools.

‘Nobody ran for a school board position to take that kind of abuse’

Sahan Journal: What kind of oversight from school boards and the governor would you like to see to make sure the right sorts of measures are being prioritized?

Osterholm: Well, I think each school board is the one that’s responsible. They need to be able to provide a report card back to parents: what they’re doing and how they’re doing it. And I think that any parent should be able to ask, “Will my child be in a room that has five to six air exchanges an hour? Are all the teachers and support staff vaccinated? Are all the kids 12 years of age and older vaccinated? What types of filtering devices are used in classrooms? What’s the density of students?”

There should be no more students in a room than at least 6 feet apart, ever. And that’s just a rule of thumb relative to how many kids are in there in terms of the air exchanges.

Sahan Journal: What are the most important things parents and kids can do to prepare for the upcoming school year?

Osterholm: Everyone that can be vaccinated, get them vaccinated. That’s absolutely critical. Number two is support your school board in doing the right things, the things we just talked about. It’s impossible not to be embroiled in the mask versus non-mask issue. And frankly, it is so challenging to see the kinds of horrible experiences that occur at school board meetings. 

Nobody ran for a school board position to take that kind of abuse. I think it’s just absolutely unfathomable. I think at this point that’s really a real issue. We need to support our schools and school boards, and they need to do the right thing to protect the students, faculty, and staff as much as possible.

‘I think you’re going to see a number of outbreaks in Minnesota schools in the weeks ahead’

The return to school comes at a time when hospital capacity is strained statewide. Osterholm pointed to an acute pediatric intensive care bed shortage statewide. A case surge in kids in schools could strain that capacity even further. The Minnesota Department of Health confirmed that statewide, very few ICU beds are available for kids.

Sahan Journal: We’re already seeing a lot of school closures and quarantines in southern states and here in Albert Lea last week. How are schools with mask mandates faring compared to schools without?

Osterholm: I can’t say. I think it’s way too early in the school year. I think you’re going to see a number of outbreaks in Minnesota schools in the weeks ahead. It’s not even an if, it’s just when and how many.

Sahan Journal: It feels like parents, schools and districts aren’t really prepared for the risks that are going to be in buildings this fall.

Osterholm: I think they’re not, and I think part of that is public health’s fault. I think we have continued to use language like “safe.” And there is nothing safe about Delta in schools. Nothing. It’s safer. We can do a lot to make the schools safer, and that’s our job. 

The question is going to be, how much safer can we make it for everyone in the school environment? And what is that going to mean in reducing the transmission? 

I know we’re going to see more cases. The question is how many more. 

We have to be honest with parents and say this is going to happen. And schools are going to need to look carefully at when they can, in a safer way, provide education, as opposed to not.

There’s this mindset right now that we have to have our kids in school at all costs because of what’s happening to them. And that’s the wrong approach. We have to have our kids in schools to learn as safely as possible so they can learn. 

Becky Z. Dernbach is the education reporter for Sahan Journal. Becky graduated from Carleton College in 2008, just in time for the economy to crash. She worked many jobs before going into journalism, including...