The new variants are coming. And right behind them, our third COVID-19 winter.
But we’re unlikely to see the ghosts of Christmases past, say experts, because these newcomers look a lot like the current virus. And our growing immunity is softening and shortening infection, limiting disease and hospitalization.
“We’ll see a surge” as people move indoors, especially if vaccination and masking rates remain low, said UC San Francisco epidemiologist George Rutherford. But, so far, there’s “no evidence … that these variants cause more severe disease.”
A stunning 300 spinoffs of the omicron variant – almost all iterations of each other, with many shared mutations — are circulating globally right now. This represents a new evolutionary phase in the pandemic. Until now, one version of the virus has been king.
Here’s the good news: The variants look a lot like the virus that was the template of our new bivalent booster, so vaccination still works. Recent infections also will be protective. The COVID virus hasn’t made a huge evolutionary leap, as it did with omicron.
“It’s not a perfect match … but it’s close,” said Jeremy Kamil, a virologist at Louisiana State University Health Sciences Center Shreveport, who studies variant mutations. “In most cases, that’s going to keep the infection in check.”
But there’s also bad news: These new variants can sneak around some therapies. The antiviral Paxlovid remains effective. But other treatments – the monoclonal antibody drugs Evusheld and bebtelovimab – aren’t. They’re too narrowly focused, so must be redesigned.
These new variants may also dodge some of the antibodies that help limit spread. “So expect high transmission,” tweeted Michael Mina, a former Harvard epidemiologist who is now the chief science officer for eMed, which sells at-home tests.
And only about 5.7% of eligible Americans, including 10% of California residents, have gotten the new booster, according to the CDC. This apathy could create serious illness if unprotected people join indoor holiday gatherings.
“The new variants that we’re beginning to see are raising a great deal of concern that we are going to see a wave,” Food and Drug Administration Commissioner Dr. Robert Califf said at a conference this month. “We can seriously mitigate that wave if the majority of people get vaccinated. That’s just not happening now.”
Meanwhile, early next year federal funding cuts will end the free distribution of COVID vaccines, treatments and tests. Already, some sites are reducing their operations. The CDC is no longer counting cases every day, so a sudden surge could be missed.
On Friday, new data showed that the virus’s family tree is splintering.
In the U.S., the sprawling “BQ” family – most notably, BQ.1 and BQ.1.1 — is gaining dominance. It’s the progeny of BA.5, which is receding. Variants BQ.1 and BQ.1.1 now represent 17% of all cases, up from only 9% last week.
We saw this coming. Since the beginning of the pandemic, the virus has multiplied quickly and randomly in hundreds of millions of people, constantly trying new ways to dodge our immune system.
“It’s a cloak-and-dagger, spy-versus-spy game,” said Kamil. “These variants that are bubbling up now are trying to get past some of our immunity.”
But the diversity is impressive. In Europe and North America, there’s an alphabet soup of new “sublineages” – BQ.1 and BQ.1.1, but also BA.2.75.2, BA.2.75.4, BA.2.3.20, BA.4.6, BJ.1, BH.1, BP.1, and more. New York, where variants are often spotted first, reports many sub-variations of BQ, such as BQ.1.3, BQ.1.14, BQ.1.2 and BQ.1.11.
In Asia, the XBB variant is causing a major new wave of cases, especially in Singapore, which has one of the world’s most highly vaccinated populations, according to Dr. Eric Topol, a professor of molecular medicine at Scripps Research in San Diego. Yet most cases are mild, even asymptomatic. XBB has a different heritage from our BQ variants; it was created by a mixing of the BA.2.10.1 and BA.2.75 strains.
Any of these variants could triumph, but regional differences suggest co-circulation over the next few months – with a tightening race between the BQ.1.1 and XBB.
Different variants may get footholds in subsets of the population, said Andrew F. Read, director of the Huck Institutes of the Life Sciences at Penn State, who studies the evolution of infectious disease.
Globally, “it is now a more diverse immune landscape,” he said. “People have gotten a variety of different vaccines and a variety of previous exposures. … They have varying degrees, and types, of immunity.”
In its effort to survive, “the virus has got to cope with that,” he said.
But despite their diversity, these new variants are all trying variations on the same genetic theme. They’ve emerged with a pattern of similar mutations. That’s called “convergent evolution” – just as birds, bats and insects all figured out how to fly, different COVID variants are using the same strategy to change a key spot in the virus where virus-blocking antibodies dock.
Scientists predicted this. In the lab, they identified which mutations – dubbed 460, 444 and 346 – would be enlisted by the virus. This involves a trade-off, they noted, so the virus is less able to latch tightly onto our cells.
Evolutionarily, “the viruses are fighting over the crumbs now,” said Kamil.
Nothing will ever put us back at square one, naïve to the virus, experts agree. These new variants can’t fully escape all components of our now-smarter immune systems.
“We’re way out of that danger zone now,” said Kamil. “But we should fully expect that there will be a fall or winter wave that’s driven by these variants. People are gathering indoors more often.
“And these viruses are continuing to find ways to eke out survival.”
Source: Orange County Register