By Apoorva Mandavilli
The holidays have come and gone, and once again Americans are riding a tide of respiratory ailments, including COVID-19. But so far, this winter’s COVID uptick seems less deadly than last year’s, and much less so than in 2022, when the omicron surge ground the nation to a halt.
“We’re not seeing the signs that would make me think that we’re heading into another severe wave,” said Caitlin Rivers, an epidemiologist at the Johns Hopkins Center for Health Security. “So far, we’re in relatively good shape.”
Still, there are few masks in sight, and just a fraction of the most vulnerable people have received the latest COVID shots, she noted.
“It’s not too late,” Rivers added. “We have not even reached peak yet for COVID, and once you reach peak, you still have to get down the other side.” That leaves plenty of time for the vaccine to provide some protection.
Federal officials are relying on limited data to measure this year’s spread. After the end of the public health emergency in May, the Centers for Disease Control and Prevention stopped tracking the number of COVID infections. The agency now has only partial access to information from states about vaccination rates.
But trends in wastewater data, positive tests, emergency department visits, hospitalization rates and deaths point to a rise in infections in all regions of the nation, according to the CDC. These patterns have prompted many hospitals to reinstate mask policies, after initially resisting a return to them this fall.
As in previous years, the numbers have steadily been rising all winter, and are expected to increase further after holiday travel and get-togethers. Many of the infections are caused by a new variant, JN.1, which has rapidly spread across the world in recent weeks.
“I think that there’s no doubt it’s helping drive, pretty substantially, this winter wave,” said Katelyn Jetelina, a public health expert and author of a widely read newsletter, “Your Local Epidemiologist.” “Unfortunately, it’s coming at the same exact time as us opening up our social networks due to the holidays,” she said, “so there’s kind of a perfect storm going on right now.”
Some scientists have pointed to rising levels of the virus in sewage samples as an indicator that infections are at least as high this year as they were at this time last year. But Rivers urged caution in interpreting wastewater data as a proxy for infections and said hospitalizations were a more reliable metric.
In the week that ended on Dec. 23, hospitalizations rose by nearly 17% from the previous week. There were about 29,000 new hospital admissions, compared with 39,000 the same week last year and 61,000 in 2021. And weekly hospitalizations are increasing more slowly than in previous years, Rivers said.
COVID is still claiming at least 1,200 lives per week. But that number is about one-third the toll this time last year and one-eighth that in 2021.
“We are in this pretty big infection surge right now, but what’s really interesting is how hugely hospitalizations have and continue to decouple from infections,” Jetelina said.
She said she worried most about hospitals buckling under the weight of multiple epidemics at once. Even in years before the pandemic, outbreaks of just influenza and respiratory syncytial virus could strain hospitals; rising COVID rates now overlap both illnesses, adding to the burden.
The CDC estimates that so far this season, there have been at least 7.1 million illnesses, 73,000 hospitalizations and 4,500 deaths from the flu.
While COVID tends to be mild in children and young adults, influenza and RSV are most risky for young children and older adults. All three diseases are particularly dangerous for infants.
Emergency department visits for COVID are highest among infants and older adults. While RSV has leveled off in some parts of the country, hospitalization rates remain high among young children and older adults.
The JN.1 variant accounts for nearly half of all COVID cases in the United States, nearly six times the prevalence just a month ago. The variant has one mutation that gives it a greater ability to sidestep immunity than its parent, BA.2.86, which was limited in its spread.
JN.1 may in fact be less transmissible than previous variants. But its immune evasiveness, coupled with the disappearance of preventive measures including masks, may explain its exponential growth worldwide, said Dr. Abraar Karan, an infectious disease physician and postdoctoral researcher at Stanford University.
Still, JN.1 does not appear to cause more severe illness than previous variants, and the current vaccines, tests and treatments work well against all of the current variants.
Experts urged all Americans — including those not at high risk of severe illness — to opt for vaccines against both COVID and flu, to use masks and air purifiers to prevent infections, to be tested and treated, and to stay home if they become ill.
Even those who do not become severely sick run the risk of long-term complications with every new viral infection, researchers noted.
“I’m not at high risk, to be honest — I’m young and vaccinated,” Rivers said. “But I continue to take precautions in my own life because I do not want to deal with that disruption, and the risk that I could develop a longer-term illness.”
Experts also urged people who develop symptoms to take a test and ask for antiviral drugs — Tamiflu for influenza, Paxlovid for COVID — especially if they are at high risk of complications.
Paxlovid is still available free of charge to most people, but many patients and even doctors avoid it out of a mistaken belief that it causes COVID symptoms to rebound, experts said. Recent studies did not find a relationship between antiviral drugs and symptom rebound.
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