A day after reporting its highest average daily Covid-19 case number, the US shattered the record on Thursday, with an average of 355,990 infections reported every day in the past week, according to Johns Hopkins University.
As the latest surge sweeps across the US, pushing cases and hospitalisations to unprecedented levels and altering daily life again, experts warn a turning point could be weeks away.
"Given the size of our country - and the diversity of vaccination versus not vaccination -- that it likely will be more than a couple of weeks (until Covid-19 cases peak) ... probably by the end of January," Dr Anthony Fauci, the nation's leading infectious disease expert, told CNBC.
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Roughly 62 per cent of the country is fully vaccinated, according to the US Centers for Disease Control and Prevention. Only about 33 per cent of fully vaccinated adults have gotten boosters, which experts say are critical to protect against severe illness from the variants.
The Omicron variant - the most contagious strain - is rapidly spreading across the world, with Australia and several European countries reporting their highest-ever case counts.
In the US, states are seeing their highest case and hospitalisation numbers ever. Some governors are calling in the National Guard.
New York reported more than 76,500 new cases Thursday, the governor's office said, breaking its single-day record. Hospitalisations hit about 8,000, an 8% spike from the day before. Hospitalizations have risen almost 20 per cent since Monday.
"Get vaccinated, get boosted, mask up and avoid large indoor public gatherings when possible," said Gov. Kathy Hochul, later announcing she was extending the mandate for businesses to have a masking or vaccine requirement to February 1.
Arkansas also set a case record, as more than 4970 residents tested positive in a day, Gov. Asa Hutchinson said Thursday. Maryland, reporting more than 10,870 new cases Wednesday, beat a state record that was set days earlier and reported its highest hospitalisation rate this week.
New Jersey, meanwhile, identified more than 28,000 new Covid-19 cases via PCR testing, Governor Phil Murphy said Thursday, "roughly quadruple from just two weeks ago, and four times as many cases than during the height of last winter's surge."
The number of positive cases is likely higher due to at-home testing, he added.
He said that as of Thursday evening, 3864 Covid-19 patients were being treated across the state, "more than double in just two weeks," the governor said, adding 70% of hospitalized Covid-19 patients are unvaccinated.
"Our hospitals right now are at roughly the same numbers they were on the worst day of last winter's surge," Murphy said. "The problem is that right now we don't see any sign of let up."
Ohio Gov. Mike DeWine is deploying 1,250 National Guard troops, he said on the day the state reported its highest hospitalization number. Georgia also deployed 200 troops in the same week that six major health systems saw 100 per cent to 200 per cent increases in hospitalizations, Gov. Brian Kemp said. New York is doubling its National Guard deployment to 100 and is preparing for 80 Guardsmen to undergo emergency medical training next month, Hochul said.
Things will get worse before they get better, one expert said.
"We know that over the next five to six weeks we're going to continue to see transmission of this virus throughout this country, much like a viral blizzard," said Michael Osterholm, director of the University of Minnesota's Center for Infectious Disease Research and Policy. "With that, we are going to see a perfect storm in our health care settings."
Child Covid-19 hospital admissions reach record-high
With more virus spreading in the country, more children are getting sick and being hospitalised than at any other point in the pandemic.
An average of 378 children were admitted to hospitals on any given day over the week ending December 28, according to the CDC and US Department of Health and Human Services.
That's a 66 per cent jump from the previous week and an all-time record, beating the one set at the end of August and early September, when an average of 342 children were admitted.
The vast majority of children admitted to hospitals are unvaccinated, said Dr Lee Savio Beers, president of the American Academy of Pediatrics.
"Where I work and practice here in DC at Children's National, about half of our hospitalizations ... are children under 5," Savio Beers said.
The number of children facing severe conditions is relatively low, but combine those with the "gigantic numbers of cases" and the percentage of unvaccinated Americans, "and I'm really worried that we're going to be in for a tidal wave of admissions, particularly for kids in the coming weeks," said Dr. Jeanne Marrazzo, a professor of infectious diseases at the University of Alabama at Birmingham.
