• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
HealthCoronavirus

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

By
Erin Prater
Erin Prater
Down Arrow Button Icon
By
Erin Prater
Erin Prater
Down Arrow Button Icon
August 11, 2023, 11:28 AM ET
With new COVID variant “Eris” (EG.5.1) rising in the U.S. and globally, you may wonder what the future holds, particularly this fall and winter. Some experts expect a peak in cases in late November, after Thanksgiving.
With new COVID variant “Eris” (EG.5.1) rising in the U.S. and globally, you may wonder what the future holds, particularly this fall and winter. Some experts expect a peak in cases in late November, after Thanksgiving.Getty Images

With new variant “Eris” EG.5.1 rising in the U.S. and globally, you may wonder what the future holds for COVID in the U.S., particularly this fall and winter.

Recommended Video

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.

The Fortune 500 Innovation Forum will convene Fortune 500 executives, U.S. policy officials, top founders, and thought leaders to help define what’s next for the American economy, Nov. 16-17 in Detroit. Apply here.
About the Author
By Erin Prater
See full bioRight Arrow Button Icon

Latest in Health

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025

Most Popular

Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Finance
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam
By Fortune Editors
October 20, 2025
Fortune Secondary Logo
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • World's Most Admired Companies
  • See All Rankings
  • Lists Calendar
Sections
  • Finance
  • Fortune Crypto
  • Features
  • Leadership
  • Health
  • Commentary
  • Success
  • Retail
  • Mpw
  • Tech
  • Lifestyle
  • CEO Initiative
  • Asia
  • Politics
  • Conferences
  • Europe
  • Newsletters
  • Personal Finance
  • Environment
  • Magazine
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
  • Group Subscriptions
About Us
  • About Us
  • Press Center
  • Work At Fortune
  • Terms And Conditions
  • Site Map
  • About Us
  • Press Center
  • Work At Fortune
  • Terms And Conditions
  • Site Map
  • Facebook icon
  • Twitter icon
  • LinkedIn icon
  • Instagram icon
  • Pinterest icon

Latest in Health

hoskins
Commentaryoffices
Gensler Co-Chair: Hot-desking was supposed to save money. It may be costing you your culture
By Diane HoskinsApril 30, 2026
2 hours ago
raw milk
Politicsmilk
Risk of paralysis, bacteria, even death is no match for Americans’ thirst for raw milk
By Laura Ungar, Jonel Aleccia and The Associated PressApril 29, 2026
17 hours ago
The Best Protein Shakes of 2026: Tasted and Approved by Nutrition Experts
HealthDietary Supplements
The Best Protein Shakes of 2026: Tasted and Approved by Nutrition Experts
By Christina SnyderApril 29, 2026
23 hours ago
aging
HealthLongevity
We’re the CEOs of Peloton and the Hospital for Special Surgery. Living longer isn’t enough, we need to live better, too
By Bryan T. Kelly and Peter SternApril 29, 2026
1 day ago
AI is changing who gets to be an expert. Are your colleagues ready to become ‘directors of intelligence’?
AIProductivity
AI is changing who gets to be an expert. Are your colleagues ready to become ‘directors of intelligence’?
By Bruce BroussardApril 29, 2026
1 day ago
Robert F. Kennedy Jr. sits at a cafeteria table with schoolchildren.
EconomyEducation
More than two-thirds of U.S. schools say they’re unable to afford the cost of student free lunch—and MAHA’s dietary guidelines may make it worse
By Sasha RogelbergApril 29, 2026
1 day ago

Most Popular

Apple cofounder Ronald Wayne—whose stake would be worth up to $400 billion had he not sold it in 1976—says that at 91, he has no regrets
Success
Apple cofounder Ronald Wayne—whose stake would be worth up to $400 billion had he not sold it in 1976—says that at 91, he has no regrets
By Preston ForeApril 27, 2026
3 days ago
‘Take the money and run’: Johns Hopkins economist Steve Hanke on why the UAE quit OPEC
Energy
‘Take the money and run’: Johns Hopkins economist Steve Hanke on why the UAE quit OPEC
By Shawn TullyApril 29, 2026
1 day ago
Jamie Dimon gets candid about national debt: ‘There will be a bond crisis, and then we’ll have to deal with it’
Economy
Jamie Dimon gets candid about national debt: ‘There will be a bond crisis, and then we’ll have to deal with it’
By Eleanor PringleApril 29, 2026
1 day ago
‘The cost of compute is far beyond the costs of the employees’: Nvidia executive says right now AI is more expensive than paying human workers
AI
‘The cost of compute is far beyond the costs of the employees’: Nvidia executive says right now AI is more expensive than paying human workers
By Sasha RogelbergApril 28, 2026
2 days ago
‘They left me no choice’: Powell isn’t going anywhere—blocking Trump from another Fed appointee
Banking
‘They left me no choice’: Powell isn’t going anywhere—blocking Trump from another Fed appointee
By Eva RoytburgApril 29, 2026
18 hours ago
More than two-thirds of U.S. schools say they’re unable to afford the cost of student free lunch—and MAHA’s dietary guidelines may make it worse
Economy
More than two-thirds of U.S. schools say they’re unable to afford the cost of student free lunch—and MAHA’s dietary guidelines may make it worse
By Sasha RogelbergApril 29, 2026
1 day ago

© 2026 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.