Questions about COVID-19 that keep Sick Kids’ infectious diseases expert up at night

Dr. Upton Allen, head of infectious diseases at the Hospital for Sick Children, remembers the winter day he started to worry about the novel coronavirus that first began circulating in Wuhan, China.

It was in mid-January, after scientists confirmed human-to-human transmission, and it became clear the virus could be easily — and quickly — transported around the world by infected passengers on airplanes.

Fast forward six months and Allen hasn’t stopped worrying about COVID-19, even as he and other physicians and scientists work to understand how the virus that causes it, SARS-CoV-2, impacts children.

Here, Allen, who has studied infectious diseases for 25 years, tells us what COVID-19 research questions keep him up at night (How do kids develop immunity to the virus?), whether parents should worry about the COVID-related Multisystem Inflammatory Syndrome in Children (no; it’s incredibly rare) and if, in his opinion, kids can safely go back to school in September (a cautious yes, but only with the proper public health precautions in place).

As much of the province moves into Stage 3 of reopening, Allen is thinking about September and the start of the school year. He said people need to continue working together to prevent an increase in the number of community cases to ensure a safe return to school.

“That said, moving forward, the threshold for closing schools again, even with an increase in the number of cases in the community, will be much higher in the fall because we have learned a lot about how we can protect ourselves,” he said. “We are a lot better equipped to deal with community cases than we were in the spring.”

Since those first worrying weeks in the winter, what has research told us about kids and COVID-19?

Number one, COVID still largely remains an adult disease. Only 7 per cent of cases in Canada appear to be occurring in individuals less than 19 years of age. (One can get into the reasons for that, but that’s where things are unknown.) Number two, there is also the observation that children appear less likely to become infected. And if they do become infected, they are less severely ill. Number three, when they are ill, they are perhaps less likely to transmit infections to others. We are still in need of more research to be sure of these three things … but the signals are pointing in that direction.

What do we know in July about kids and COVID that we didn’t know in March, when the WHO declared a global pandemic?

The key point is that things are still evolving. But we do have a clearer understanding of the spectrum of COVID illness. Initially, we thought COVID was just a respiratory illness but now it does appear that it’s more than that. We now know it also involves the gastrointestinal tract. We now have more atypical forms of presentation beyond respiratory symptoms. We’ve seen the appearance of things like “COVID toes” that are skin manifestations of presumably COVID illness. We’ve also seen the development of the Multisystem Inflammatory Syndrome in Children. In March we didn’t know about this.

Can you briefly explain the new Multisystem Inflammatory Syndrome in Children (MIS-C) that appears to be linked with COVID-19?

This a condition where children seem to have an excessive immune response to the SARS-CoV-2 virus that lags behind the time when the person was acutely ill. It’s likely a post-infectious syndrome, meaning that it appears weeks after the initial acute SARS-CoV-2 infection when active infection is no longer present. Tests can show where inflammation is happening in various parts of the body. This syndrome resembles another entity called Kawasaki syndrome, which involves inflammation of blood vessels, including in some cases the blood vessels connected with the heart.

How worried should parents be about MIS-C?

This is so rare; it’s really important for parents to put that in perspective. I would not spend a lot of time being worried about it. I do know that it’s hard to tell a parent not to worry … but it’s incredibly rare. And when it does occur, it does seem that we can treat it.

What do scientists most want to know about this syndrome?

We need a better understanding of why it’s happening and if it truly is related to COVID. One theory is that the body, rather than having a careful, measured immune response to the virus, overshoots and triggers this syndrome. We need to know if this is true, whether there are other triggers and how to identify the syndrome quickly.

For you, what is right now the biggest unanswered question about kids and COVID — if you could snap your fingers and find out something definitively?

Number one would be the antibody responses. Do children develop adequate antibody responses? Are these antibody responses sustained and do they relate to protection? In other words, would the antibody responses neutralize and knock out the virus? We need more work in this area.

We also need a better understanding of the ability of children to become infected and transmit infection or virus under different circumstances. For example, if somebody gets infected within the home, versus in the community, is there a difference in how severely ill they become? Is there a difference in how much virus they have on board to transmit it? These are things we need some more work to help to better understand.

Why is it important to understand the body’s antibody response when it comes to a virus like SARS-CoV-2?

Get the latest in your inbox Never miss the latest news from the Star, including up-to-date coronavirus coverage, with our email newsletters Sign Up Now

Looking at the body’s antibody response provides us with some insights into whether or not infection resulted in future protection. Also, whether this protection is sustainable — so how long is the protection for? It is long-lasting or for a short period of time?

This is the question most parents are asking right now in Ontario and so I’ll ask it of you: If you have children, would you send them to school full time in September?

I would say: Yes. The overriding principle is that one should look at the risks versus benefits, at the time. It really does appear there are significant downsides or disadvantages to not having kids do their usual thing, like going back to school. We need to focus on how to get kids back to school safely. I realize there is a lot of heated discussion in that regard. But ultimately it boils down to a risk versus benefit tradeoff. Based on the information we currently have, it seems to me we can develop enough of a plan that would allow kids to safely return to school.

What public health measures are needed to ensure schools are safe?

Even prior to a case occurring within any setting, schools will need some sort of COVID screening measure. Screening, in this particular case, shouldn’t mean asking students questions as they stand in a line, going into school; that may not be practical. Instead, how might you engage families to feel empowered, so they can monitor their children for onset of respiratory symptoms? And if a child does become symptomatic, that they are then rapidly tested, the appropriate contact tracing is done and isolation, as per regular public health guidance.

Given what we know now about our current public health infrastructure, do we have the resources to ensure some 2 million kids can safely go back to school?

I do think we have the infrastructure. It’s important to recognize that it might not necessarily be a one-size-fits-all approach for all areas across the province and for all schools. Some additional resources might need to be directed at certain areas, for example, at so-called hot zones. But I think we have the infrastructure and personnel to handle return-to-school, I do.

What do you want to say to parents who are anxious about COVID-19, now and in September for the start of school?

I would say that current evidence and research suggest to us that children are not usually the ones who get severely ill, though they can. Their illness is usually mild. That’s an important point to bear in mind. So parents can rest assured their child will have a good outcome, even if that child ends up with COVID-19. That’s a really important message to get across to parents: If my child gets COVID, the overwhelming evidence suggests they will have a good outcome.

Much of the province has now entered Stage 3 (with the exception of the GTA and some other parts of southern Ontario). Does this stage, which involves indoor dining, bars and cinemas, give you any pause for how we get children back to school in the fall?

It certainly causes one to pause and think. We want kids back to school full time. So how might we, as a society, work together to ensure that happens? How might we learn from the mistakes that have happened in some other parts of the world, notably the United States, to prevent this (an increase in community cases) from happening to us? We have to work together to try to reduce the risk of a major upswing in the number of cases ahead of the fall.

This interview has been edited for length and clarity.