Bivalent Vaccines Protected Kids, Even if They Had Been Infected Already

A new study finds moderate protection from the bivalent booster in kids.

It was only four years ago when we called the pathogen we now refer to as “the coronavirus” nCOV-19. It was, in many ways, more descriptive than what we have today. The little “n” there stood for “novel” — and it was really that little “n” that caused us all the trouble.

You see, coronaviruses themselves were not really new to us. Understudied, perhaps, but, with four strains running around the globe at any time giving rise to the common cold, these were viruses our bodies understood.

But the coronavirus discovered in 2019 was novel, not just to the world, but to our own immune systems as well. Different enough from its circulating relatives that our immune memory cells failed to recognize it. Instead of acting like a cold, it acted like, well, at the time, like nothing we had seen before. At least in our lifetimes. The story of the pandemic is very much a bildungsroman of our immune systems — a story of how our immunity grew up.

The difference between the start of 2020 and now — where infections with the coronavirus remain common but not as deadly — can be measured in terms of immune education. Some of our immune systems were educated by infection, some by vaccination, and many, by both.

When the first vaccines emerged in December of 2020, the opportunity to educate our immune systems was still huge. Though, at the time, an estimated 20,000,000 had been infected in the US and 350,000 had died, there was a large population that remained immunologically naïve — I was one of them.

If 2020 and early 2021 was the era of immune education, the post-vaccine period was the era of the variant. From one COVID strain to two, to five, to innumerable, our immune memory — trained on a specific version of the virus or its spike protein — became imperfect again. Not naïve — these variants were not “novel” in the way COVID-19 was novel — but they were different. And different enough to cause infection.

Following the playbook of another virus that loves to come dressed up in different outfits, the flu, we find ourselves in the booster era — a world…