Covid-19 vaccines for children: Why the Pfizer and Moderna data supports it


That’s why, when officials meet, they will weigh up a complicated set of factors. What are the chances that a child will be infected with covid? How much protection does a vaccine provide? What are the potential symptoms and complications children face from taking it? 

Taking all these questions into account, says Blumberg, “it’s clear the benefits outweigh the risks for this age group.”

In fact, the trial data and analyses showed that in almost every covid scenario, vaccinating children will prevent severe infection and death, with very little risk.

What the studies found

Pfizer’s study, which started in March 2021, took nearly 2,300 children and gave two-thirds of them a two-dose vaccination regimen, while the others got a placebo. Shots were given 21 days apart and, crucially, at a lower dosage than those for older people—a third of the amount of vaccine.

From the study, three vaccinated children caught covid, while there were 16 cases among the placebo group—almost 91% effectiveness. Side effects were typical and generally mild, and myocarditis, the heart inflammation that has been seen as a rare side effect and has probably caused most concern, didn’t even appear (rates among adults run at around seven per million, so 2,300 is a very small sample size).

Moderna, meanwhile, said on Monday that its studies on children under 12—with two shots at half the adult dosage given 28 days apart—also show strong results. That vaccine will not be up for discussion when the FDA meets, and will have to go through the same approval pathway that Pfizer is currently on before it can be given to children.

The bottom line is that these studies have shown that vaccinations reduce children’s chances of symptomatic covid infection and hospitalization in line with adult numbers—and without notable complications.

Could vaccinating children help curb the pandemic?

Vaccination is not just about individual benefits, however, although those are obviously important. On a broader level, says computational epidemiologist Maimuna Majumder, vaccinating children could have an impact on the shape of the pandemic itself.

“One thing that makes school age children––especially younger kids––unique is not only the number of contacts they have on a given day but also the heterogeneity of age groups among those contacts,” says Majumder, who is a faculty member at Boston Children’s Hospital and Harvard Medical School. “They interact with their peers at school and at extracurriculars, but they also interact with older educators and care-providers, as well as their families.”