The Atlantic Daily: A Guide to Mixing COVID Boosters

Should you switch brands or stick with your original?

Hand holding vaccine
Paul Ellis / AFT / Getty

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This week, “mix and match” booster shots got two big thumbs up—but the strategy needs one more, from CDC Director Rochelle Walensky, to become official policy. In discussions today, CDC representatives hinted that the agency may express a preference for same-brand boosting, my colleague Katherine J. Wu told me, but wouldn’t actively discourage mixing.

Brand mixing, if approved, opens up nine different vaccination paths. Maybe you go Pfizer-Pfizer-Pfizer. But what about Pfizer-Pfizer-Moderna?

To help you explore your options, my colleague Rachel Gutman and I put together this choose-your-own-adventure guide to vaccine mixing and matching.

Before you scroll, we need to alert you to one big caveat. Our data on this, which come from an NIH study that Rachel covered in detail, is very preliminary and looks only at antibodies—an imperfect proxy for immunity. We’re still waiting on other kinds of data, and longer-term studies. Consider this a snapshot of where things stand for now.

I got Pfizer.

Right now, you can get a booster six months after your second dose if you’re 65 or older, immunocompromised, at high risk of severe disease, or have a high risk of COVID exposure because of your living or working situation.

  • If you’re eligible: Looking to maximize your antibodies? That very preliminary research would suggest you mix it up and try Moderna. But a third Pfizer dose would probably be just as good for your immune protection. Johnson & Johnson did not perform as well in antibody counts—but if you had a bad reaction to your first round of Pfizer doses or are a young man concerned about myocarditis, talk with your doctor about whether you should opt for J&J this time.

  • If you’re not eligible: Don’t sweat it. You probably don’t need a boost yet!

I got Moderna.

Congrats! You got what looks like the top-performing vaccine as of now, at least when we measure antibodies. Your booster still needs a formal CDC recommendation. Right now, it appears only people over 65, immunocompromised people, and those who the CDC defines as high-risk will be eligible.

  • If you end up being eligible: To maximize your post-booster antibodies, early evidence suggests you stay the course and get a third Moderna shot. Switching to Pfizer is the next-best option. If you had a reaction to an earlier mRNA shot or are a young man worried about myocarditis, you and your doctor might consider Johnson & Johnson. But generally, that brand produced fewer antibodies.

  • If you’re not eligible: Hang tight! Your immunity is probably doing just fine for now.

I got Johnson & Johnson.

You might’ve had a stressful past few months while the mRNA vaccines hogged the spotlight. But now there’s good news: The CDC is poised to recommend that anyone over 18 get a booster two months out from their initial dose. (Because kids were never authorized, that means everyone who got J&J.)

  • Because you’re likely to be approved: In that study on antibodies, a two-shot course of J&J produced the fewest. So you probably want your second shot to be an mRNA one (Moderna or Pfizer). Moderna has a slight edge, but the difference between that shot and Pfizer doesn’t really matter. If you’re a young man concerned about the myocarditis risk from an mRNA vaccine, talk with your doctor about whether another J&J shot is a better way to balance your risks. If you’re a young woman, you’re probably safer getting Moderna or Pfizer, given that J&J can increase your risk of rare but dangerous blood clots.

Collage of Steve Bannon
Getty; The Atlantic

The rest of the news in three sentences:

(1) The U.S. House voted to hold the former Trump aide Steve Bannon in contempt for refusing to comply with a subpoena. (2) Snap stock took a nose dive. (3) Former President Donald Trump launched his own social-media platform.

Today’s Atlantic-approved activity:

Give up on your dream of being famous. It’s better for your well-being. “Despite how much we desire it, fame is terrible for happiness,” Arthur C. Brooks warns in his latest column.

A break from the news:

Explore this extraordinary collection of wildlife photography.


Every weekday evening, our editors guide you through the biggest stories of the day, help you discover new ideas, and surprise you with moments of delight. Subscribe to get this delivered to your inbox.