Health Care

US sees COVID resurgence as JN.1 variant becomes dominant

COVID-19 antigen home tests indicating a positive result are photographed in New York, April 5, 2023.

The U.S. is riding another wave of rising COVID-19 infections, as holiday gatherings and a new variant are driving increased transmission. 

According to the Centers for Disease Control and Prevention (CDC), the wastewater viral activity level for COVID-19 is the highest it’s been since the omicron surge in 2022.  

At the same time, a new variant called JN.1 has become the most dominant strain and was responsible for about 44 percent of infections nationwide by mid-December, a sharp rise from about 7 percent in late November.

Infectious disease experts say hospitals have plenty of capacity, and many infections are relatively mild. While numbers are ticking higher, the country isn’t experiencing a major surge.

Still, the CDC can’t track the actual number of infections, especially since most people either test at home or don’t test at all. So experts say wastewater is one of the more accurate warning signs. The Midwest is experiencing the highest levels of viral activity.  


The agency reported 29,000 hospitalizations in the week before Christmas, compared with 39,000 in 2022. Week-over-week emergency department visits were up 12 percent in the same period.

Since Thanksgiving, about 1,400 people a week on average have been dying because of COVID-19.   

The numbers have been steadily rising all winter, prompting some hospital systems to resume mask mandates. Still, vaccination rates with the latest COVID-19 shot are extremely low and infectious disease experts are concerned for the most vulnerable.  

Only about 19 percent of adults have received the latest shot, according to the CDC, though data limitations may mean the number is slightly higher.  

“When you get so much transmission throughout the general population, the virus will find the more fragile people, the people who are not vaccinated with the latest updated vaccine … those people are at the higher risk and are more likely to require hospitalization,” said William Schaffner, an infectious disease specialist at Vanderbilt University Medical Center. 

According to a CDC report from Dec. 22, the virus remains “a serious public health threat,” especially for older adults, infants, people with compromised immune systems or chronic medical conditions and people who are pregnant.

Nursing homes are among the most vulnerable to COVID-19 outbreaks, but only about 33 percent of long-term care facility residents were up to date with their COVID-19 vaccinations, according to a December CDC report.  

Biden administration officials from the Department of Health and Human Services (HHS) met with nursing home industry leaders Wednesday to discuss the low vaccination rates.  

Katie Smith Sloan, president and CEO of LeadingAge, an association of nonprofit aging service providers, said she urged HHS to ease logistical issues that are barriers to uptake, such as enabling single-dose vaccine orders for nursing homes, coordinating vaccines being offered through hospitals on discharge and communicating more directly with residents and families. 

“It’s also vital the HHS recognize and acknowledge that nursing homes are part of the larger community. When vaccination uptake rates are woefully low among the general public, it’s critical that public health officials educate the public more broadly — to the benefit of the entire nursing home sector and their surrounding communities,” Smith Sloan said in a statement. 

Schaffner said the high levels of viral activity are partly due to seasonality — with holiday celebrations, travel and cold weather pushing people to congregate indoors — and because the JN. 1 variant is likely more transmissible.

Part of the problem is that people may not be isolating if they have the virus, because they can’t or won’t test. So if someone assumes they have a cold, it could be COVID.

The federal government largely stopped giving out free COVID-19 tests at the end of the public health emergency, and employers may be less willing to accommodate COVID-related absences.

“Now that the tests have to be purchased, and they’re reasonably expensive, I think a lot of people are developing symptoms, making assumptions about their illness, but not getting tested, I think, in part so that they don’t have to keep themselves isolated at home,” Schaffner said.