We’re Asking the Next Booster to Do Too Much


America’s first-ever reformulated COVID-19 vaccines are coming, very ahead of schedule, and in some ways, the timing couldn’t be better. Pfizer’s version of the shot, which combines the original recipe with ingredients targeting the Omicron subvariants BA.4 and BA.5, may be available to people 12 and older as early as the week after Labor Day; Moderna’s adult-only brew seems to be on a similar track. The schedule slates the shots to debut at a time when BA.5 is still the country’s dominant coronavirus morph—and it means that, after more than a year of scrambling to catch up to SARS-CoV-2’s evolutionary capers, we might finally be getting inoculations that are well matched to the season’s circulating strains. Which is “absolutely great,” says Deepta Bhattacharya, an immunologist at the University of Arizona.

In other ways, the timing couldn’t be worse. Emergency pandemic funds have been drying up, imperiling already dwindling supplies of vaccines; with each passing week, more Americans are greeting the coronavirus with little more than a shrug. The most recent revamp of the country’s pandemic playbook has softened or stripped away the greater part of the remaining mitigation measures that stood between SARS-CoV-2 and us. Calls for staying up-to-date on COVID vaccines are one of the last nationwide measures left—which puts a lot of pressure on shot-induced immunity to combat the virus, all on its own.

The nation has latched on before to the idea that shots alone can see us through. When vaccines first rolled out, Americans were assured that they’d essentially stamp out transmission, and that the immunized could take off their masks. “I thought we learned our lesson,” says Saskia Popescu, an infectious-disease epidemiologist at George Mason University. Apparently we did not. America is still stuck on the notion of what Popescu calls “vaccine absolutism.” And it rests on two very shaky assumptions, perhaps both doomed to fail: that the shots can and should sustainably block infection, and that “people will actually go and get the vaccine,” says Deshira Wallace, a public-health researcher at the University of North Carolina at Chapel Hill. As fall looms, the U.S. is now poised to expose the fatal paradox in its vaccine-only plan. At a time when the country is more reliant than ever on the power of inoculation, we’re also doing less than ever to set the shots up for success.

In terms of both content and timing, the fall shot will be one of the most important COVID vaccines offered to Americans since the initial doses. Since SARS-CoV-2 first collided with the human population nearly three years ago, it’s shape-shifted. The coronavirus is now better at infecting us and is a pretty meh match for the original shots that Pfizer, Moderna, and Johnson & Johnson produced. An updated vaccine should rejuvenate our defenses, prodding our antibody levels to soar and our B cells and T cells to relearn the virus’s visage.

That doesn’t mean the shots will offer a protective panacea. COVID vaccines, like most others, are best at staving off severe disease and death; against BA.5 and its kin, especially, that protection is likely to be durable and strong. But those same shields will be far more flimsy and ephemeral against milder cases or transmission, and can only modestly cut down the risk of long COVID. And when partnered with a compromised or elderly immune system, the shots have that much less immunological oomph. Then say a new immunity-dodging variant appears: The shots could lose even more of their strength.

Vaccine performance also depends on how and how often the shots are used. The more people take the doses, the better they will work. But no matter how hard we try, this reformulated shot “is not going to cover everyone, either because they choose not to get it or won’t be able to access it,” says Katia Bruxvoort, an epidemiologist at the University of Alabama at Birmingham. People who haven’t yet finished their primary series of COVID shots aren’t expected to be able to sign up for the BA.5 boosts—a policy that Bhattacharya thinks is a big mistake, not least because it will disadvantage anyone who seeks a first brush with vaccine protection this fall. “The better the degree of breadth right at the beginning,” he told me, the better future encounters with the virus should go. Most kids under 12 remain in that totally unvaccinated category; even those who have completed their initial round of shots won’t be eligible for the revamped recipe, at least not in this first autumn push. Among people who can immediately get the new booster, uptake will probably be meager and unbalanced. “Realistically, the boosters are going to be concentrated in the places that have been the least impacted by the pandemic” and in people who have already had at least one boost, says Anne Sosin, a public-health researcher at Dartmouth. Such widening gaps in protection will continue to offer the virus vulnerable pockets to invade.

Crummy uptake isn’t a new issue, and some of the same deterrents that have plagued rollouts from the start haven’t gone away. Vaccines are a hassle and can come with annoying side effects. And in recent months, even more obstacles have been raised. The wind-down of COVID funding is making it much harder for people without insurance or other reliable health-care access to get boosted. And after nearly three years of constant crisis slog, far fewer people fear the virus, especially now that so many Americans have caught it and survived. A year into the Biden administration’s concerted push for boosters, fewer than a third of U.S. residents have nabbed even their first additional shot. With each additional injection Americans are asked to get, participation drops off—a trend experts anticipate will continue into the fall. “There’s a psychological hurdle,” says Gregory Poland, a vaccinologist at the Mayo Clinic, “that this is over and done.”

The reality that most Americans are living in simply doesn’t square with an urgent call for boosts—which speaks to the “increasing incoherence in our response,” Sosin told me. The nation’s leaders have vanished mask mandates and quarantine recommendations, and shortened isolation stints; they’ve given up on telling schools, universities, and offices to test regularly. People have been repeatedly told not to fear the virus or its potentially lethal threat. And yet the biggest sell for vaccines has somehow become an individualistic, hyper-medicalized call to action—another opportunity to slash one’s chances at severe disease and death. The U.S. needs people to take this vaccine because it has nothing else. But its residents are unlikely to take it, because they’re not doing anything else.

If all goes as planned, COVID tests, treatments, and vaccines will be commercialized by 2023—making these fall shots perhaps the last free boosters we’ll get. And yet, officials have neither a new strategy for buoying vaccine uptake nor the ammunition for clear messaging on how well the shots will work. In service of speeding up the availability of the BA.5-focused shots, federal regulators are planning to green-light the new formulation based on antibody data from mice. (Both Pfizer and Moderna have human studies planned or under way, but results aren’t expected to be ready until after the rollout begins.) The reliance on animal experiments isn’t necessarily concerning, Bhattacharya told me; the approval protocol for annual flu shots doesn’t require massive human clinical trials either. But the shortcut does introduce a snag: “We know nothing yet about the efficacy or effectiveness of these Omicron-focused vaccines,” Poland said. Researchers can’t be sure of the degree to which the shots will improve upon the original recipe. And public-health officials won’t be able to leverage the concrete, comforting numbers that have been attached to nearly every other shot that’s been doled out. Instead, communications will hinge on “how much trust you have in the information you’re getting from the government,” UNC’s Wallace told me. “And that is very tricky right now.”

Shots, to be abundantly clear, are essential to building up a properly defensive anti-COVID wall. But they are not by themselves sufficient to keep invaders out. Like bricks stacked without a foundation or mortar, they will slip and slide and crumble. Nor is a wall with too few bricks likely to succeed: If the goal is to preemptively quell a winter case surge, “a booster that will have maybe 30 to 40 percent uptake is not something we can expect to have a huge population-level impact,” Bhattacharya told me.

All of that bodes poorly for the coming fall and winter, a time when respiratory viruses thrive and people throng indoors. The nation could see yet another round of “incredibly high surges,” says Jessica Malaty Rivera, a senior adviser at the Pandemic Prevention Institute, further sapping supplies of underutilized or tough-to-access tools such as tests and treatments, and straining a health-care system that’s already on the brink. Cases of long COVID will continue to appear; sick people will continue to miss work and school. And “God forbid we get another variant” that’s even more severe, George Mason’s Popescu told me, further overwhelming the few defenses we have.

Pinning all of America’s hopes on vaccines this fall, experts told me, may have ripple effects on our future COVID autumns too. Asked to counter the virus alone, the injections will falter; they will look less appealing, driving uptake further down. If this fall is meant to set a precedent for subsequent vaccination campaigns, it may unspool one of the worst scenarios of all: asking shots to do so much for us that they hardly accomplish anything at all.


Source link

Recommended Posts

No comment yet, add your voice below!

Add a Comment