​‘That’s what I care about as a parent’: Why Dr. Faust is encouraged by Moderna’s vaccine for young children

"I'm pretty sure my kid WILL get Covid at some point, vaccine or not. But with a vaccine beforehand, she's far less likely to suffer for very long at all."

A healthcare worker administers a dose of the Pfizer-BioNTech Covid-19 vaccine to a child at an Oklahoma County Health Department Vaccine Clinic in Oklahoma City, Oklahoma, Nov. 17, 2021. Nick Oxford/Bloomberg

More than a year after vaccines started being available for most people, the youngest among us are still not eligible. That might soon change, and for Dr. Jeremy Faust it can’t come soon enough.

Yesterday Moderna asked the Food and Drug Administration to authorize its COVID vaccine for children under 6 years old. Pending the actual data, Faust, a Boston physician, public health researcher, and parent, said on Twitter they will vaccinate their 4-year-old daughter “ASAP” and it “will have a massive impact” on how his family lives their lives.

The vaccine measured to be 51% effective against symptomatic COVID for children ages 6 months to two years and 37% effective for ages 2 to 6.


Though these numbers may not inspire huge confidence at first glance, Faust said that the reality may be “MUCH better than that.”

Faust pointed to the way the vaccines were designed and said it’s “not really about infection.”

“What these vaccines have been shown to really do, over and over, is protect against severe disease and hospitalization, longterm consequences,” Faust wrote. “A pediatric trial can’t be large enough to detect that. But the ‘immune bridge’ strategy used both by Moderna and Pfizer has worked.”

The “immune bridge” strategy Faust is referring to involves looking at immune markers to infer vaccine efficacy — so rather than focusing solely on positive tests, it looks at if an immune response is generated by the vaccine.

“So to me, it’s huge news that they reached the antibody levels needed to imply solid protection against long-term consequences,” Faust wrote. “That’s what I care about as a parent. I’m pretty sure my kid WILL get Covid at some point, vaccine or not. But with a vaccine beforehand, she’s far less likely to suffer for very long at all.”

Faust said he will “be quite comfortable” getting his daughter vaccinated with the Moderna vaccine. If Pfizer releases data that is “TONS better” than Moderna’s before Modera’s is authorized, he said he might consider waiting a few more weeks. 


“But at this point, this virus is so contagious, that the sooner you have your kid vaccinated, the better,” Faust wrote. “Getting protected sooner is what matters. It’s unlikely that there will be such differences between 3-dose Pfizer and 2-dose Moderna, though we’ll need to see.”

Read Faust’s full thread here:


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