CDC tracker and map show the spread of the new COVID-19 variant

The COVID subvariant JN.1 is rapidly surging across the U.S., according to just-released projections from the Centers for Disease Control and Prevention (CDC). Based on the available but limited data, JN.1 is now estimated to account for 44% of cases across the country over the past two weeks—even greater in New Jersey and New York State. All this, as the country heads into consecutive holiday weekends when gatherings with friends and loved ones could put many, particularly the elderly and people with underlying medical conditions, at even higher risk.

Here’s what you need to know about JN.1 COVID subvariant as you head into the weekend and holiday travel.

It’s the new subvariant of COVID-19 that has surged over the past four weeks. Many COVID variants come and go as the virus mutates, but JN.1 has the distinction of now making up an estimated 44.2% of new cases in the United States over the past two weeks, based on limited available data. According to the CDC’s map, JN.1 makes up an even larger number of cases in the Northeast, at 56.9%. (These numbers could shift as more data becomes available.)

On December 19, the World Health Organization (WHO) listed JN.1 as a “variant of interest” in its latest global COVID surveillance update. Variants of interest have the potential to become “variants of concern,” in global health nomenclature, indicating mass spread that results in deaths and hospitalizations. The CDC notes that, at this point, JN.1 does not appear more dangerous than other Omicron variants. “The continued growth of JN.1 suggests that it is either more transmissible or better at evading our immune systems,” the department says. “At this time, there is no evidence that JN.1 presents an increased risk to public health relative to other currently circulating variants.” 

Is JN.1 a version of Omicron?

The JN.1 COVID subvariant is a version of Omicron, as was the EG.5 subvariant that spiked across the U.S. in August. The Omicron COVID lineage has been the dominating family of COVID-19 mutations in the U.S. since the COVID Delta lineage surged from late 2020 into 2021.

What are the symptoms of JN.1?

NBC News notes that doctors in recent weeks have seen COVID-19 patients with mild symptoms like a sore throat and eventual congestion—more similar to other respiratory illnesses than some earlier, and stranger, COVID symptoms, such as a loss of taste or smell accompanied by a hacking dry cough. In more severe cases, lack of oxygen circulation can lead to shortness of breath, chest pain, or blue- or gray-ish coloration of lips and beneath nail beds.

JN.1 is just the latest threat in a pathogenic trifecta responsible for rising respiratory illness across the U.S. and the world at large—the others include influenza type A (H1N1) and RSV. Influenza type A alone has led to a 200% rise in hospitalizations for flu-like illness across all age groups in the past four weeks, according to available CDC data. 

Vaccinations and the latest booster shots remain key to protection against any and all viruses, including JN.1—but it come with some caveats. Initial data from Moderna and Pfizer (awaiting peer-review) shows that the currently available COVID booster shots against the XBB.1.5 strains also build up antibodies against JN.1. But keep in mind that it typically takes upwards of seven days from vaccination to antibody production that would provide the level of immunity to help prevent the virus’s spread. 

With so many different viruses going around, a multipronged defense is the safest course: Getting vaccinated is one of the best ways to boost your own protection and the possibility of infecting others. If you haven’t already, the CDC, WHO, FDA, and other public health organizations recommend getting the seasonal flu shot and the latest available COVID booster; and for adults ages 60 and older, an RSV vaccine. (The RSV vaccine is also recommended for certain pregnant women, infants, and toddlers, as are two monoclonal antibodies that protect against RSV in some infants and toddlers up to 24-months. Best advice: talk with your obstetrician or pediatrician.) Find the FDA’s full recommendations on RSV vaccines and monoclonal antibodies.

Additional recommendations include wearing masks during indoor mass gatherings, in airports, and on planes and public transport. And if you wake up with a sore throat or start to feel ill at any time, take an at-home over-the-counter COVID-19 test.