- A new COVID-19 variant has been detected in the U.S.
- JN.1 is causing a growing number of cases around the world.
- There are concerns that the variant is very infectious.
SARS-CoV-2, the virus that causes COVID-19, is mutating yet again. The latest variant getting buzz is JN.1, which the Centers for Disease Control and Prevention (CDC) flagged in a report issued late last week.
In the report, CDC officials say that they’re “learning” about JN.1, noting that it’s not overly common in the U.S. right now. Still, infectious disease experts say there’s a reason why this variant was flagged—and why researchers are keeping an eye on it.
So what is JN.1 and why is it getting attention right now? Here’s everything you need to know about the latest variant.
What is JN.1?
JN.1 is a COVID-19 variant that descended from BA.2.86, explains infectious disease expert Amesh Adalja, M.D., a senior scholar at the Johns Hopkins Center for Health Security. JN.1 is “another Omicron variant,” he says.
“BA.2.86 has more than 20 mutations on the spike protein and there was a concern when it was first detected a while back that, wow, this might be a real problem,” says Thomas Russo, M.D., professor and chief of infectious diseases at the University at Buffalo in New York.
JN.1 has an additional mutation on its spike protein from BA.2.86, which is what SARS-CoV-2 uses to latch onto your cells and make you sick, Dr. Russo says.
JN.1 symptoms
As of now, there’s no data to suggest that JN.1 causes different symptoms than previous COVID-19 variations, says William Schaffner, M.D., a professor at the Vanderbilt University School of Medicine. “It’s an Omicron variant and looks to be similar,” he says. In case you need a refresher, the CDC says those symptoms may include:
- Fever or chills
- Cough
- Shortness of breath or difficulty breathing
- Fatigue
- Muscle or body aches
- Headache
- New loss of taste or smell
- Sore throat
- Congestion or runny nose
- Nausea or vomiting
- Diarrhea
How contagious is JN.1?
That’s still being determined. “There is some data that suggest JN.1’s parent BA.2.86 may be more transmissible than previous variants,” Dr. Russo says. “Since JN.1 is a derivative of BA.2.86, there is a concern that it may be more transmissible.”
But Dr. Adalja points out that, while there were a lot of concerns around BA.2.86 when it was first detected, it didn’t really spread. “There’s no evidence that this variant—at this time—is going to behave any different,” Dr. Adalja says.
Should we be worried about JN.1?
As of right now, JN.1 only makes up less than 0.1% of COVID-19 viruses, per the CDC. That said, it’s gaining steam in other countries.
“JN.1 has been described in a number of countries, including the U.S., Iceland, Portugal, Spain, and the Netherlands,” Dr. Russo says. “It’s also increasing in frequency in France—it seems to be taking off.”
JN.1 also has a mutation on its spike protein that “seems to make it much more immune evasive than its parents,” Dr. Russo says, adding that the variant is “quite devious.”
JN.1, like BA.2.86, is different from other strains, too, Dr. Russo says. “As a result, we may be at risk of getting more infections,” he says.
Will the COVID-19 vaccine protect against JN.1?
It’s hard to say at this point. The CDC notes that the spike protein is the part of the virus that vaccines target and, as a result, the updated COVID-19 vaccine should work against JN.1. The CDC also points out that existing data show that the updated 2023-2024 COVID-19 vaccines help our immune systems block BA.2.86. “We expect JN.1 will be similar,” the CDC says.
“The updated vaccine is closer to JN.1 than our old vaccine,” Dr. Russo says. “The hope is that, even if we see more cases with JN.1, the updated vaccine will protect against severe disease.”
How to protect against JN.1 and other variants
JN.1 and other COVID-19 variants are out there and will continue to swirl around, Dr. Adalja says. “This is an endemic respiratory virus,” he says. “It is one of the viruses that humans will always deal with.”
But Dr. Schaffner says there are things you can do to lower your risk of getting sick. “Please take advantage of” the updated COVID booster, he says. “Its acceptance has been so dismal across the country. We in public health and infectious diseases are very concerned about that.”
If you’re considered high risk for COVID-19 complications, Dr. Schaffner says it’s time to consider wearing a mask again. “If you’re going to the supermarket, religious services, a concert…whenever you’re in public indoor spaces with other people, put that mask back on,” he says.
And, if you happen to get COVID-19, contact your doctor to see if you qualify for an antiviral medication. “The key thing is to make sure that high-risk individuals are protected with updated vaccines and are quickly prescribed an antiviral if they become infected,” Dr. Adalja says.
Korin Miller is a freelance writer specializing in general wellness, sexual health and relationships, and lifestyle trends, with work appearing in Men’s Health, Women’s Health, Self, Glamour, and more. She has a master’s degree from American University, lives by the beach, and hopes to own a teacup pig and taco truck one day.
