A swarm of sneaky omicron variants could cause a COVID-19 surge this fall

Mutations showing up in many variants help the coronavirus evade our immune defenses

An illustration of a large green coronavirus, with a purple and red coronavirus breaking through the right half of the larger virus. The backdrop is multicolored scan lines on the left half and plain gray on the right

As we head into our third pandemic winter, researchers are keeping an eye on a swarm of omicron variants that have donned sneaky disguises to get around our immune systems.

Andriy Onufriyenko/Getty Images

Fall and winter have not been kind to us over the last couple of years.

In 2020, cases of COVID-19 began to climb in October. And at this time last year, we were in the calm before the storm, so to speak, with delta-driven case counts slowly dipping before the omicron variant began its road to global domination at the end of November (SN: 12/1/21). What will happen in our third pandemic winter, as omicron continues to evolve and many people ditch their masks?  

Only time will tell. But already there are some warning signs that we could be faced with yet another wave of infections, hospitalizations and deaths. For one, cases and hospitalizations are increasing in some European countries, including the United Kingdom.

What happens across the pond usually portends what will happen in the United States. At the national level and in most states, cases are still going down. But experts worry that may not hold true for long, as temperatures drop and more people gather indoors where the coronavirus is more likely to spread. Some Northeastern states, for instance, have seen a sharp increase in coronavirus levels in wastewater, suggesting there has been an uptick in transmission even if it’s not yet reflected in official case counts (SN: 4/22/22).

There’s also a wild card this year, complicating matters. New versions of omicron abound. How might they shift the pandemic’s near future? 

It’s a hard question to answer. On one hand, we’re in a very different place than we were two years ago, or even last year, with more treatments on hand and an omicron-specific booster (SN: 5/11/22; SN: 9/2/22). But the coronavirus has been known to throw us a few curveballs. Experts expect that winter will usher in yet another wave, but what it will look like and how high it will crest is unclear.

“Although we can feel good that we are going in the right direction, we can’t let our guard down,” said National Institute of Allergy and Infectious Diseases director Anthony Fauci at an October 4 webinar held by the University of Southern California Annenberg Center for Health Journalism in Los Angeles.

There is some good(ish) news: Most people have been exposed to the virus, whether through vaccination or — the less-desirable route — an infection, or both. That means our immune systems have the virus’s mug shot on hand. Our antibodies and T cells are trained to kick into high gear if the coronavirus trips any alarm bells as it enters our noses, throats or lungs. 

These immune barriers can dampen the virus’s ability to spread among people, as well as protect many from becoming seriously ill. As a result, fewer people may end up in the hospital or dying compared with previous years. 

But then there’s the bad news: Over the last year, the omicron variant has adopted a few disguises in the form of mutations that help the virus hide from our immune systems. Over the summer, a version called BA.5 rose to dominance, pushing out its relatives BA.2 and BA.2.12.1. Now, researchers are keeping tabs on a new alphanumeric motley crew of omicron versions.

It is possible that a new worrisome variant could suddenly appear and outcompete all its relatives, as the delta and omicron variants did in 2021. The next name on the list would be “pi.”

But another — perhaps more likely — possibility is that over the next few months, our attention won’t be focused on a single lineage that sweeps the world but on a swarm of new variants. That’s thanks in part to the arms race between our immune systems and the virus.

Now that so many people have some kind of protection, compared with in 2020 or early 2021, the coronavirus must constantly change in ways that poke holes in those defenses in order to spread. Some variants circulating now have independently acquired the same mutations, imparting similar abilities to dodge antibodies in lab tests, researchers report in a preliminary study posted October 4 at bioRxiv.org. With multiple variants using the same tactics to get around people’s immune systems, it can be tough for a single variant to come out on top. 

Two of the newest omicron versions, BQ.1.1 and BA.2.75.2, are particularly adept at dodging some individual antibodies taken from people who had recovered from a BA.2 or BA.5 infection, the researchers found. That means some people may be more susceptible to another infection if the new versions, which are so far present at low levels in the United States, spread widely this fall. 

Officials have already taken some steps to tackle this ever-changing virus. This fall, Pfizer/BioNTech and Moderna released tweaked versions of their mRNA vaccines that tackle both the original version of the coronavirus and omicron to give immune systems a refresher course. But few of these updated shots are making it into arms. Half of U.S. adults say they have heard little to nothing about COVID-19 boosters, according to a Kaiser Family Foundation poll released September 30. And so far, only around 4 percent of people age 12 or older have gotten the new jabs. (On October 12, the U.S. Food and Drug Administration and Centers for Disease Control and Prevention signed off on bivalent boosters for 5- to 11-year-olds.)

What’s more, omicron’s continued evolution means that vulnerable people are fast losing COVID-19 treatment options. The October 4 study, which has not yet been peer-reviewed, also found that the last stronghold of antibody drugs that are used to treat or protect high-risk patients — therapies called bebtelovimab and Evusheld — didn’t recognize some of the new variants when tested in lab dishes. And on October 3, the FDA warned that Evusheld, which is used as a preexposure treatment to protect immunocompromised people, doesn’t work for all variants. The drug still offers protection against many of the currently circulating variants, the FDA said, as does the antiviral Paxlovid.  

Another unknown that we’re facing this winter is how much other respiratory infections might add on to an already COVID-heavy burden. Flu season in Australia, usually a bellwether for those of us north of the equator, was back after a two-year hiatus and got an earlier than usual start. Experts are once again warning about a possible “twindemic” in the Northern Hemisphere, with both influenza and the coronavirus making people ill (SN: 9/18/20). Not to mention, there are myriad other infections that most people haven’t been exposed to over the last couple of years thanks to masking and social distancing.

That’s not to say everyone needs to prepare for yet another lonely winter. But it’s a sobering reminder that taking extra precautions such as testing before social gatherings and masking — especially around vulnerable people — would be wise, even as we get on with our lives. And that reminds me: I need to order more masks.

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