With ‘Eris’ rising and now ‘Fornax,’ when are COVID cases likely to peak again? A look at what may lie ahead for fall and winter

As of Friday, another new player is more officially in the mix: “Fornax,” or FL.1.5.1, an Eris relative named after a constellation in the southern hemisphere. That’s according to Ryan Gregory, a biology professor at the University of Guelph in Ontario, who has been assigning “street names” like Kraken to high-flying variants.

FL.1.5.1 is the top variant currently reported in New York, considered a bellwether state by variant trackers. There, wastewater levels and hospitalizations are rising, notes Raj Rajnarayanan—assistant dean of research and associate professor at the New York Institute of Technology campus in Jonesboro, Ark.—and a top COVID-variant tracker.

Nationwide, wastewater levels—currently our best way to gauge viral activity—have seemingly crested into a relatively small half-wave. They’re certainly dwarfed by the Delta, Omicron, and “Kraken” XBB.1.5 surges of old. But the current swell hovers higher than wastewater levels at past low points in the pandemic, including spring of last year and even May of 2020.

In short, the damned thing’s still very much with us.

On the heels of Eris are a handful of other variants trackers are eyeing that could buoy or elevate levels to greater heights.

Regardless, cases will likely peak in late November, shortly after the Thanksgiving holiday, Rajnarayanan says.

From tsunamis to high sea levels

A post-Thanksgiving peak is typical for the virus, owing to holiday gatherings. Gregory agrees with the forecast. But in many ways, the landscape of the pandemic has changed from earlier days, he says.

From COVID’s introduction to humans in late 2019 through the initial Omicron wave in January 2022, “you kind of have big, distinct, sharp waves, a big peak that went up fast and came down fast, driven by an individual variant—Alpha, Delta, Omicron,” he tells Fortune.

Courtesy of Biobot Analytics

But since last summer, there “just hasn’t been that pattern anymore.”

Instead, a new cadence developed—and it’s likely to continue this fall and winter. It’s one of a high wall of cases sustained by mini-waves of multiple new variants overlapping each other—one slicker, faster, sleeker Omicron spawn after the next.

It’s all about the “high sea level rather than tsunamis,” says Gregory.

Courtesy of Biobot Analytics

A coming shift in pandemic paradigm

We’ll certainly see new variants and mutations this fall—and we may see a shift in the COVID vernacular, too. While variant nicknames like Eris, Arcturus, and Kraken have made headlines of late, the conversation will likely focus on names of problematic mutations, such as ones that make the virus more transmissible or more severe. Successful variants will likely pick up the same mutations.

Already, there are a couple of mutations variant trackers are eyeing, for their ability to further evade immunity—and to infect human cells even better when combined.

“The data are pretty clear that we’re heading into a lot more [variants with such mutations] in the weeks and months ahead,” says Dr. Eric Topol, a professor of molecular medicine at Scripps Research and founder and director of the Scripps Research Translational Institute.

He expects Eris (EG.5.1) to continue to grow in the near term; it’s “not going to lose steam yet,” he says. Then we’ll likely see variants with those extra-concerning mutations take hold.

Vaccines to the rescue?

Updated XBB.1.5 vaccines—matched to the dominant strain of this past winter—will reportedly be available by the end of September. And they should be a fairly good match, experts say, effective at preventing severe outcomes like hospitalization and death—and could help squash the predicted late-November peak.

But Gregory and Rajnarayanan worry that many, if not most, Americans will choose to forgo the new jabs. It’s thought that only 27% of adults and 18.5% of adolescents had received an Omicron booster as of late last year, according to a survey conducted by the CDC.

With the pandemic emergency state officially over, according to the WHO and CDC, even fewer might this time around.

“I don’t think people will line up to take the vaccines,” Rajnarayanan said.

Topol is concerned that the vaccines won’t come soon enough for the immunocompromised and elderly.

If new boosters were “coming out imminently next week, or by the end of the month, that would be okay,” he said. “But if you wait until September, October, schools are starting. By then we’re already seeing wastewater levels rise.”

“We have a wave that’s brewing now.”

A tripledemic in the making?

As to whether the country will experience another “tripledemic” of COVID, flu, and RSV this fall as it did last year, Michael Osterholm, director of the University of Minnesota’s Center for Infectious Disease Research and Policy, says there’s no reason to worry at the moment—and no way to truly tell.

The southern hemisphere, which has seasons opposite ours, didn’t see big surges in COVID during their winter, Osterholm says, which bodes well for winter in the northern hemisphere. The flu season there, too, was average.

Last year, some scientists attributed the so-called tripledemic to COVID, RSV, and flu surging after pandemic mitigation measures like masking and social distancing were dropped. Society, having wrapped itself in proverbial bubble wrap for several years, was paying off an “immunity debt.”

But Osterholm points to a similar situation that occurred during another pandemic, the H1N1 bird flu of 2009. The flu waxed and waned on its own, and peaked again in the fall. As it did, RSV, H3N2 flu, and influenza B suddenly “disappeared”—just as RSV and the flu did earlier in the COVID pandemic.

The difference between the two scenarios: There were never any mitigation measures like masking that could have caused the viruses to recede during H1N1. Scientists still can’t explain why they did. One theory: that competitive viruses like COVID and H1N1 flu are able to “cancel out” other viruses for periods of time, he says.

The pandemic is nearing its fourth anniversary and continues to evolve—and some days Osterholm thinks he knows less about the pathogen than he did two years ago.

“I still sleep with one eye open all of the time because of COVID,” he says.