Editor’s Note: Dr. Stephen Kessler is a physician in Phoenix, Arizona. He and his wife wrote an open letter to Arizona Gov. Doug Ducey regarding the reopening of schools that received coverage by CNN, NPR, and The Arizona Republic. The opinions expressed in this commentary are his. View more opinion articles on CNN.
Sometime in the spring of 2020, an intriguing idea started circulating in epidemiologic circles. As the early literature started trickling in regarding the transmission of SARS-CoV-2 by children, some prominent academics began espousing what can fairly be referred to as the “Magic Virus Hypothesis.”
The thinking went something like this: In addition to children generally having very mild disease with Covid-19, they were also very unlikely to spread the virus.
This was an astonishing hypothesis because it ran contrary to everything we know about the transmission of traditional respiratory viruses, such as influenza and the common cold, which, of course, is often caused by a type of coronavirus. With these traditional viruses, children are recognized as significant drivers of transmission.
The radical nature of the hypothesis should have resulted in a pause for serious reflection by responsible scientists and physicians. Instead, it was quickly seized upon and amplified by highly respected medical journals.
On May 5, the normally staid British Medical Journal (BMJ) published an editorial titled “Children are not Covid-19 super spreaders: time to go back to school.” The official journal of the American Academy of Pediatrics (AAP) quickly followed suit with a similar commentary, “Covid-19 Transmission and Children: The Child is Not to Blame.” Both advocated for the reopening of schools, with the editorial from the BMJ going so far as to argue that, “Governments worldwide should allow all children back to school regardless of comorbidities.”
Never mind the paucity of the available research at the time, nor the fact that the few existing studies had serious deficiencies in their methodology. Not to mention the presence of conflicting evidence.
The magic virus evangelists marched on.
On June 25, the AAP issued a statement in which they forcefully advocated for the reopening of schools. They noted that, “Although children and adolescents play a major role in amplifying influenza outbreaks, to date, this does not appear to be the case with SARS-CoV-2…children may be less likely to become infected and to spread infection.”
Phrases like “does not appear” and “may be less likely” were technically accurate but dangerously cavalier. It is reckless to rely on a handful of small, inconclusive epidemiologic studies to overturn the acquired knowledge of a century of research on virology.
Politicians bent on reopening schools seized on these recommendations, culminating in Secretary of Education Betsy Devos’ claim on July 15 that “more and more studies show that kids are actually stoppers of the disease and they don’t get it and transmit it themselves.” Devos received widespread criticism for her remarks, but, in essence, her comments were merely a rearticulation of those of the AAP without the qualifiers.
In mid-July, researchers in South Korea published what is perhaps the largest and most well-designed study to date on the transmission of Covid-19 by children. They found that children aged 10-19 do, in fact, spread Covid-19 just as effectively as adults, with children younger than 10 contributing to a lesser degree.
What effect did this new research have on the magic virus evangelists? They merely adjusted the magic virus age demographic downward to accommodate the latest findings.
This included the AAP, who, as of August 21, amended their initial statement to read, “Children younger than 10 years may be…less likely to spread infection.”
What caused the initial embrace of the radical idea that children under 18 do not contribute to the spread of Covid-19, as well as its equally radical revision? I don’t have the answer, but my guess is that it is a combination of things.
But equally to blame is a lack of intellectual rigor in examining the methodologies of the existing research on the spread of Covid-19 by children. Any physician or scientist can tell you that the strength of the conclusions that can be drawn from a piece of research rely firmly on the methodology of the study. And the existing research has plenty of flaws.
Put differently: Why might studies find lower transmission of SARS-CoV-2 by children if the transmission rate were in fact the same as that by adults? In general, the reason lies in the fact that children with Covid-19 often have very mild symptoms, if they have any symptoms at all. As a result, they are much less likely to be tested during the acute phase of the virus, when they are most likely to test positive. And if they were to pass the virus on to their parents or other adults in the household, their nasal passages may be clear of viral RNA by the time they are tested, in which case the virus may be presumed to originate from an adult host.
Couple this with the fact that pediatric testing is incredibly difficult to come by in many communities, and it is easy to see why it is challenging to get an accurate accounting of the amount of Covid-19 infection in children, as well as its spread.
Of course, it may turn out that SARS-CoV-2 is indeed a magic virus, in which transmission by children is exceedingly rare. If that happens, no one would be more delighted than I. But currently, there is no one alive who can declare that with any certainty. Not the experts at the Centers for Disease Control, nor the World Health Organization. Not even Dr. Anthony Fauci himself.
And that is exactly the point.
If you are going to argue that a novel respiratory virus is transmitted in a radical new way, the bar to making that claim should be formidable.
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It has been shown that young children harbor similar or higher viral loads of SARS-CoV-2 in their upper airways as those found in older children and adults. Given this, as well as our acquired knowledge of the transmission of other respiratory viruses, the default assumption must be that children are equally as infectious as adults. The responsibility of the researcher is to prove that hypothesis wrong, not vice versa.
To argue otherwise is potentially dangerous. Especially when those arguments are being used by policy makers to guide the reopening of schools and other children’s activities.
With that being said, here’s hoping the magic virus hypothesis holds.