New COVID boosters could mark turning point in pandemic

·West Coast Correspondent
·11-min read

While many Americans say they’re over COVID-19, the virus doesn’t seem to have taken the hint. Instead, it’s been spinning off new variants and subvariants at a furious pace and continuing to infect hundreds of thousands of people every day.

But now that frantic pattern could finally be coming to an end — and (fingers crossed) the more predictable COVID future we’ve been promised could be on its way.

As early as Wednesday, the Food and Drug Administration is expected to authorize new Pfizer and Moderna booster shots tailor-made to fight the Omicron subvariants that have been triggering the vast majority of new U.S. COVID cases for months. A combined 175 million doses should be available shortly after Labor Day.

Registered nurse Jeremy Oyague administers a COVID booster shot to a patient.
Registered nurse Jeremy Oyague administers a COVID booster at a vaccination clinic in Los Angeles. (Christina House/Los Angeles Times via Getty Images)

That moment, in turn, will mark an important milestone. It will be the first time since the start of the pandemic that the vaccine has been updated to target the latest version of the virus — and the first time this year that the virus itself has stopped evolving so fast that we can’t keep up.

Which means that if current trends hold — admittedly a huge “if” — fall 2022 may prove to be the beginning of the endgame that Americans have been awaiting for two and a half years: a more stable, sustainable coexistence with COVID.

In contrast, consider all the upheaval we’ve endured since the ultra-transmissible Omicron variant first emerged in South Africa last November. By mid-December, the initial version of Omicron — BA.1 — had displaced Delta in the U.S.; average reported cases soon skyrocketed to 800,000 a day, the most ever. With mutations that helped it spread fast and dodge immunity, Omicron crowded out all other competitors for three and a half months, until the end of March 2022.

Then, just when it seemed like things were calming down, another more transmissible Omicron strain materialized: BA.2. It reigned supreme for two months, from the end of March to the end of May — only to be overtaken by the even more infectious BA.2.12.1, which dominated for a month, from the end of May to the end of June.

Then came BA.5, the most transmissible and evasive Omicron subvariant yet.

Microbiologists with the Aegis Sciences Corporation process COVID-19 and monkeypox tests.
Microbiologists with the Aegis Sciences Corporation process COVID-19 and monkeypox tests at a facility in Nashville. (Nathan Posner/Anadolu Agency via Getty Images)

That’s four consequential new coronavirus mutations in as many months — a dizzying trajectory for a pandemic that had produced just four significant new variants, total, over the previous two years. As a result, more than “half of all COVID infections have happened” in 2022, according to the New York Times.

“The rise of the BA.5 variant is an outgrowth of accelerated evolution of the virus,” Dr. Eric Topol, founder of the Scripps Translational Institute and a leading COVID expert, wrote in a Los Angeles Times op-ed in July, describing the shift as “quite rapid and unlike the first year of the pandemic.”

“BA. 5 puts the nail in the coffin of the myth that the virus will evolve into a milder form and fade away,” Topol continued. “We could easily see more variants — indeed a whole new family with more extensive immune evasion and growth advantage — in the months ahead.”

And yet ... we haven’t.

Topol wasn’t wrong to warn about new variants; again and again, the virus has zigged when we hoped it would zag. But four weeks ago, BA.5 accounted for about 82% of new U.S. COVID cases, according to the Centers for Disease Control and Prevention; today BA.5 is responsible for about 88% of new cases. A full two months after it took over, no newer subvariant seems poised to displace it.

That’s a promising development. Epidemiologists and virologists have known for some time that COVID isn’t going away, so eradication is off the table. The big questions then become: (a) how often will disruptive new versions of the virus crop up? and (b) how ready will we be when they do?

Heading into the fall, “I agree that things look favorable, without an imminent variant going into exponential growth and [with] a BA.5 vaccine,” Topol told Yahoo News. “But that’s a ~6-8 week forward look, and we can’t project beyond that — so there’s still no room for complacency.”

Shoppers on a crowded market street in Los Angeles in July.
Shoppers on a crowded market street in Los Angeles in July. (Irfan Khan/Los Angeles Times via Getty Images)

Experts tend to describe the future of COVID in three ways. The worst-case scenario is more “emergence events” like Omicron, in which a radically mutated new variant comes out of nowhere and drastically neutralizes prior immunity. The more often this happens — and the more effectively these left-field variants dodge protection against serious disease — the more dangerous this scenario could be.

The middle-ground scenario should also sound familiar; it mirrors the last few months. In this model, disruptive new subvariants seem to emerge constantly, and because they’ve evolved to infect people with at least some prior immunity, the average level of infection remains stubbornly high, with only minor variations by season.

And then there’s the most optimistic scenario. Here the virus starts to settle into a sort of flulike stability. A very transmissible version arises, perhaps as summer turns to fall. It infects a lot of people — but vaccination, treatment and prior exposure keep it from killing as readily as its predecessors. Immunity rises as a result. Seasonal booster shots tailored to this specific iteration of the virus help as well. Other strains continue to circulate, but they struggle for traction in light of all that fresh immunity. By the time a newer version does take off — through some combination of mutations in the virus and waning protection in the population — another year or so has passed. And we’re ready to counter it with reformulated boosters.

Again, any of these scenarios could still come to pass. But what’s striking about the current moment is how closely it resembles the last, best one.

People line up for COVID-19 vaccines at a clinic in San Rafael, Calif.
People waiting for COVID-19 vaccines at a clinic in San Rafael, Calif., in April. (Justin Sullivan/Getty Images)

Earlier this summer, the FDA and the CDC decided to abandon the federal government’s previous fall booster plan, which involved targeting the original Omicron BA.1 strain. Regulators added BA.4 and BA.5 to the new formula instead.

At the time, Dr. Anthony Fauci, President Biden’s chief medical adviser, warned that the change was merely a “best guess” to hit a “moving target.”

“There’s always the possibility that you’re going to have the evolution of another variant,” Fauci admitted. “Something entirely different.”

Topol was more blunt. “By the time a BA.5 vaccine booster is potentially available, who knows what will be the predominant strain?” he wondered.

But now the BA.5 booster is almost ready — and somewhat unexpectedly, nothing has come close to unseating BA.5.

That doesn’t mean nothing ever will. Other iterations of Omicron continue to arise. In India, for instance, BA.2.75 triggered a summer bump in cases by displacing BA.5. But in the U.S., its initial growth rate was about half of BA.5’s, and as a result it has barely registered. BA.4.6 is more prevalent right now — it accounts for about 7.5% of all U.S. cases, concentrated mostly in the Midwest — but it too has been growing a lot slower than BA.5 did, taking about a month to double as a share of all cases, whereas BA.5 initially took a week. According to evolutionary biologist Tom Wenseleers, “Omicron BA.4.6 [has been] short-lived virtually everywhere” it has appeared.

Experts are also watching a new version of BA.5 called BA.5.2.1.7 (or BF.7), which has some advantageous mutations.

Signs in a store window read: Stop! Someone inside is immunocompromised! and Masks are required.
Signs in a store window in Lawrence, Kan., in May. (Michael Siluk/UCG/Universal Images Group via Getty Images)

Yet for now, at least, none of these Omicron subvariants seems like the sort of big leap forward over BA.5 that BA.5 was over its predecessors — particularly in the face of an ever-growing U.S. immunity wall built from BA.5 infections, BA.2.12.1 infections, BA.2 infections, BA.1 infections and the forthcoming BA.4 and 5 booster, all of which will make it harder for less radical new variants to trigger new surges. According to one recent study, the “effectiveness of a previous Omicron infection against symptomatic BA.4/BA.5 reinfection was 76.1%.”

This means that, finally, the U.S. is heading into the coldest months of the year — the ones that typically see the worst waves of COVID and other respiratory viruses — with a well-matched vaccine and lots of fresh protection. If every fall looks like this going forward, we’ll be in much better shape than in the past.

But will every fall look like this going forward? It’s impossible to say. The virus has surprised us many times before; the next devastating mutation could still emerge. (Experts say, though, that the longer Omicron and its descendants dominate, the lower the chances are of some totally different variant replacing it.)

And even if we get lucky and avoid those pitfalls, the pandemic’s current, seemingly more “sustainable” trajectory remains a serious challenge for millions of people. Rampant infections will always be disruptive, forcing Americans to miss school and work; a not-insignificant share of cases still trigger long COVID. Far fewer Americans got boosters compared with their first vaccine shots (and federal funding to distribute shots has dried up). Immunity wanes a lot faster for older people than younger people, so seniors remain vulnerable (as do the immunocompromised); even now, 475 Americans are dying from COVID every day. That’s a rate of nearly 175,000 annual COVID deaths — more than triple a bad flu year.

Health care workers wearing face shields treat a COVID patient in an ICU.
Health care workers treat a COVID patient in the ICU at Hartford Hospital in Hartford, Conn., in February. (Allison Dinner/Bloomberg via Getty Images)

Unless something changes, that tragic toll is likely to be part of our collective COVID future as well. Earlier this month, Trevor Bedford, a computational virologist at the Fred Hutchinson Cancer Center in Seattle, sketched out a rough model comparing how the virus would circulate seasonally given different rates of people getting infected, building immunity and then gradually becoming susceptible to infection again (either because of new variants or because their immunity has worn off). With a “flu-like ~5 year rate of waning,” Bedford explained on Twitter, “we get winter epidemics and summer troughs” — a lot like the flu.

But “if what we've seen with Omicron evolution in 2022 becomes largely the norm,” Bedford continued, then that would imply a 1.8-year rate of waning — which means “year-round variant-driven circulation” with higher winter peaks and much less variation between winter and summer. In an interview with the New York Times, Bedford estimated that — given current trends — “every year, around 50 percent of Americans will be infected and more than 100,000 will die.”

“A hundred thousand deaths is more than the annual toll of any other infectious disease and would make COVID-19 a top-10 cause of death in the country,” the Times’s David Wallace-Wells continued. “It’s a few multiples of a typical flu season and more than die each year from diabetes, pneumonia or kidney disease.”

The hope is that today’s respite means the worst of Omicron’s mutations are behind us, and no new mutant emerges anytime soon. But hope is one thing; complacency is another. In the meantime, Americans — particularly older Americans — should get boosted to protect themselves. Ventilation should be upgraded, experts say. Those same experts argue that masks and tests should be free and widely available, and that research on long COVID treatments should continue. And the government should push harder for nasal and variant-proof vaccines that can stop infection before it starts.

Reaching a stable, sustainable COVID future isn’t just about what the virus does from here on out. It’s about what we do, too.