So… Should I mix and match my booster?

The mixing and pairing of vaccine brands is officially on the table in the United States. But this option could soon be presented as the choice of List B.

Yesterday evening, the director of the CDC Rochelle Walensky Green lighted booster shots from Moderna and Johnson & Johnson, the long-awaited follow-up to a similar recommendation given to the Pfizer formulation last month. In the current state of approval, anyone who qualifies for an extra jab – which now includes tens of millions of additional Americans – should be able to choose which brand of booster they like. But discussions between a panel of experts who advised Walensky have hinted at a catch: the agency has yet to release its final clinical guidelines on who, in particular, might want to step up with what – and a first draft of the recommendations suggests that Americans “should” stick to the same mark they got on their first try.

Switching to another plan would be allowed, as was the case FDA cleared Wednesday; according to the CDC’s draft guidelines, people may choose to mix and match based on availability or preference, after weighing their individual risks and benefits. (As a reminder, FDA clearances tell Americans which vaccines they are allowed to receive. The CDC is following this with advice on people. should do with these options.)

So the CDC’s stance on mixing and pairing could end up being relatively smooth, neither elation nor excoriation. It might also be the most practical course of action for the agency, given the variables involved and the lack of clear evidence that could unravel them. But the recklessness of Choose anything is confusing as hell.

Consider, first of all, the large number of choices now available to Americans eligible for the recall (a limited set of mRNA recipients and everyone who got J&J). With three approved or licensed vaccines, the simplest mix-and-match matrix has nine possible combos. But that’s an underestimate of the absolutely unmanageable number of variations there. Moderna’s third shots, for example, are coming full doses for immunocompromised people and half doses for everyone. The timing of additional injections may also matter: People who receive a second injection of J&J six months after their first injection appear to be produce more antibodies than people who wait only two months. Obviously, inoculation is not just about the vaccines you get. It’s about which vaccines, when, how many, how many times, in what order, over and over again – an absolute multiverse of choice. Add to that the inevitable differences between individual immune systems and start to imagine the terror of the resulting flowchart. In this chaotic and evil backdrop, the CDC’s tentative preference for homogeneity has some appeal, even as it establishes a slightly judicious juxtaposition between what is written in the book and, essentially, what Mavericks might do, if they want to.

Read: Should you mix and match your booster dose?

Then again, maybe what the CDC is saying is, at this point, somewhat moot. Millions of people have already boosted, some of them before eligibility. Now, with even more choices available, “people who care will be voting with their feet,” Celine Gounder, an infectious disease physician at Bellevue Hospital in New York, told me. This may in the CDC guide is easy to grasp and use. For anyone who has made a decision, in any direction, the agency’s relatively passive approach is not that helpful (or hard to ignore).

There are certainly advantages to cross-stimulating vaccines. People won’t have to worry about matching marks between doses; people in risk groups may be able to avoid the rare and specific side effects of injections. The strategy could even be more protective. None of this, however, makes it easy to select a booster. As it stands, the decision requires a little leap of faith, or at least some immunological inference. Data on mixing and pairing are still relatively scarce, although first evidence It looks promising. A recent National Institutes of Health study have found that changing strokes seems to extract antibodies at least as well, and in some cases a little better, than staying the course with a single mark. This seems especially true for the OG J&J crowd: mRNA boosters spiked antibody levels, compared to a second serving of J&J. (One caveat: the study was bolstered with the full dose of Moderna, not the half-dose allowed by the FDA for non-immunocompromised people.) If this pattern holds, J&J already has the least vaccine. popular in the United States, could become even more of an outsider vaccine.

It’s not sure. Gounder advises caution: the NIH study was small, according to a imperfect proxy protection in less than 500 people for a very limited period of time. Boghuma Kabisen Titanji, infectious disease physician and researcher at Emory University in Atlanta, is a little more optimistic and told me that she finds the mix-and-match data compelling enough to come up with the strategy. The trends in the NIH study, she pointed out, appear well online with the month of The data which came out of places like the United Kingdom, which adopted a hybrid approach very early on, but for original doses and with a different set of brands (Pfizer and AstraZeneca).

Ideally, the blending and pairing could blur the brand lines between vaccinated Americans, thus collapsing us further into the same. fairly well protected Bowl. (Did you have Pfizer or Moderna? J&J? Who cares?) Or, it could split us into endless subgroups that are getting harder and harder to compare.

Collecting good data on vaccine responses becomes increasingly difficult as inoculation becomes more personalized. With so many Americans now ready to choose their own vaccine adventure—you know how they may– the differences between the plans could become more difficult to pinpoint. We need this data: what we learn now will hopefully help us design better, safer and more effective vaccine regimens for future generations. But if fewer people embark on similar trajectories, they could become more difficult to group together. The studies may need to be more limited in scope or work harder to combine data from different parts of the country. It’s not impossible, said Saad Omer, vaccine expert and epidemiologist at Yale. But that makes things “more difficult”.

Part of that beta testing vibe dates back to last winter, when experts passionately debated the merits to skip or delay the second doses of Pfizer and Moderna vaccines. Some countries, including the United Kingdom, have spaced out the shots; the United States and others stuck to the very small gaps prescribed by the tests. The delay was a gamble, as it left people partially protected longer and sent mixed messages to a frustrated audience. But now it seems beneficial. Really, we were all guinea pigs – and this round of massive stimulation sets us up for a new wave of bewilderment.

We will not all be winners; someone should always be in the worst-performing group. Here again, “worse” is always relative. Anyone who plays the booster game is already, technically, fully vaccinated, which puts them in front of the billions of people around the world who still aren’t. Titanji pointed out that more Americans got boosters that people received the first doses in Nigeria, a country of some 200 million people.

Even in the United States, getting more first shots at people is still the highest priority– that’s how we collectively contain the coronavirus. But the hyper-individualistic American approach pandemic is once again pushing us to forge our own course. The government kind of shrugged its shoulders on the mix-and-match and gave us the decision: choose whatever path you think is right; go to page 7; hope for the best. Here’s the trick, however, no one really knows where this chapter ends. Good luck, I guess.