Understanding the new Covid-19 variant, Eris
The formally named EG.5 is making the rounds, but we don't have to worry just yet


A new Covid-19 variant has entered the scene, becoming the most prevalent strain in the U.S. However, it may not be as dangerous as the ones that came before.
The new variant, Eris (formerly called EG.5), accounts for approximately 17% of new Covid cases, according to an estimate by the Centers for Disease Control and Prevention. It's a subvariant, or "spinoff," of the XBB strain of the Omicron variant of the virus, per CNN. "Omicron is out there making minor variations. It's having children, progeny, but they're all closely related to omicron," Dr. William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt University Medical Center, told ABC News. Eris has been reported in several countries and is rapidly spreading in the U.S., proving to be "slightly more resistant to neutralizing antibodies in [the] serum of infected and vaccinated persons," Dr. David Ho, a professor of microbiology and immunology, said in an email to CNN.
Should we be worried?
"At this time, there is no evidence indicating EG.5 is able to spread more easily, and currently available treatments and vaccines are expected to continue to be effective against this variant," a CDC spokesperson told Politico. The symptoms are also similar to the variants that came before, including "sore throat, runny nose, congestion, cough and fever."
The Week
Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

Sign up for The Week's Free Newsletters
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.
While not more severe, it's most likely spreading quickly due to human activity. Record heat is keeping people indoors, prompting faster spread of infection. Globally, people have resumed travel, causing higher levels of exposure to Covid. "I do expect that there will be widespread infections, and I would expect that those widespread infections would generally be mild," said Dr. Dan Barouch, an immunologist and virologist at Harvard University, to CNN. Global hospitalizations have gone down since the beginning of the year, and the World Health Organization (WHO) officially declared the end of the pandemic in May 2023. "The people who are at high risk for severe disease, obviously, have to continue to take precautions," stated the WHO.
"It basically has some more immune escape compared to the ones that were precedents in this XBB series," Dr. Eric Topol, a cardiologist at the Scripps Translational Research Institute, told CNN. "It has an advantage, which is why it's getting legs all around the world." However, since Covid numbers were already low, the uptick isn't an automatic cause of worry. "If you take a low number and you talk about it in terms of percent increase, it's going to sound a lot scarier than it is, right?" Dr. Shira Doron, the chief infection control officer for Tufts Medicine, told ABC News.
How can we prevent the spread?
The best way to avoid contagion is to get tested and get the vaccine. The CDC is expected to release a new Covid booster shot this coming fall, and "vaccination continues to be the best way to protect against severe outcomes of Covid-19," the CDC spokesperson told Politico. If you test positive, experts recommend staying home and masking up if you need to go out. The new strain doesn't seem to have more severe impacts than those before it.
"We are going to see some uptick in cases because that new variant replaces the old one … and so what we see is a small uptick, but we're still at the lowest levels we've ever seen," Doron explained. The WHO also actively monitors strains of Covid. "Having this surveillance system for strains of Covid out there around the world is a way for us to be on the alert should a new distinctly different mutation suddenly appear and start to spread in any country, not just in the U.S.," Dr. William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt University Medical Center, told ABC News. "We would get advance notice, and we could start to prepare for that."
A free daily email with the biggest news stories of the day – and the best features from TheWeek.com
Devika Rao has worked as a staff writer at The Week since 2022, covering science, the environment, climate and business. She previously worked as a policy associate for a nonprofit organization advocating for environmental action from a business perspective.
-
The new Stratus Covid strain – and why it’s on the rise
The Explainer ‘No evidence’ new variant is more dangerous or that vaccines won’t work against it, say UK health experts
-
‘Nightmare bacteria’ are rapidly spreading
Under the radar The infections are largely resistant to antibiotics
-
Kissing bug disease has a growing presence in the US
The explainer The disease has yielded a steady stream of cases in the last 10 years
-
Climate change is making us eat more sugar
Under the radar Sweets make the heat feel more manageable
-
Trump makes unmoored claims on Tylenol and autism
Speed Read No causal relationship has been established between autism and acetaminophen use during pregnancy
-
RFK Jr. vaccine panel advises restricting MMRV shot
Speed Read The committee voted to restrict access to a childhood vaccine against chickenpox
-
Quit-smoking ads are being put out
Under the radar The dissolution of a government-funded campaign could lead to more smokers in the future
-
Sloth fever shows no signs of slowing down
The explainer The vector-borne illness is expanding its range