Screen the Kids!

Those little humans who are not (yet) eligible for a coronavirus vaccine may prolong the pandemic.

F. Perry Wilson, MD MSCE
6 min readApr 29, 2021


As we face a new struggle to get covid-19 vaccination rates up in this country, we need to remember that there is a group of people with virtually zero vaccine uptake. This group often congregates together in indoor gatherings, coming into close physical contact for extended periods. Fully 24% of Americans are part of this group.

We call them children.

And, as I am putting this together, there is currently no FDA authorized vaccine for kids.

Might that population of children form the reservoir for subsequent COVID outbreaks? While data is pretty clear that safe school re-openings don’t drive community COVID-19 positivity rates, there is still concern that kids — who are more likely to be asymptomatic — may become vectors of infection anyway. Are they our Achilles heel, and if so, short of authorizing some vaccines for them, is there anything we can do about it?

A new paper in JAMA Network Open suggests we need to be screening kids for asymptomatic infection. We need to be doing it now, and we need to be doing it fast.

Now, this is a simulation study — a complex set of mathematical models that operate under varying assumptions. As an empiricist, I tend to favor real-world evidence, but simulations can be useful — particularly when they reveal relatively large effects that are robust to a bunch of assumptions — and that’s what we have here.

This might be slightly simplified :-)

Ok here’s the setup. Assume you have a population of adults and kids, age distribution exactly like that of the US. COVID-19 is spreading in that population at a certain rate (we can play with that rate, called the effective reproduction number — in the base case they use 1.2 meaning that on average each infected person infects 1.2 additional people). This is the sort of transmissibility we see now given good social distancing and masking — but new variants and loosening of restrictions could push it higher.



F. Perry Wilson, MD MSCE

Medicine, science, statistics. Associate Professor of Medicine at Yale University. New book “How Medicine Works and When it Doesn’t” available now.