(CNN) At one Los Angeles hospital there are five tents outside, one serving as a waiting room.
So many patients are coming into Martin Luther King Jr. Community Hospital some are being put in the gift shop, a chapel or a conference room.
Over the past week, almost 100,000 coronavirus cases have been reported in Los Angeles County, and that causes problems for what do with other patients.
Hospital CEO Dr. Elaine Batchlor told CNN on Monday: "If we continue to see an increase in the number of Covid patients, we may be forced to do something that, as health professionals, we all really just loathe having to even think about."
She was talking about rationing care. Right now, it's not business as usual.
"Our staff has been incredibly adept and flexible in accommodating increasing numbers of patients, so as you heard, we have five tents outside of the hospital," Batchlor said. "We have patients in our conference room, in our chapel."
Many gurneys are taken into the gift shop, she said.
While Batchlor didn't specify how many new patients have Covid, the increase in their numbers is putting stress on all care.
Batchlor said the hospital will not turn patients away but may have to employ techniques that have been used during war.
"We use what in the battlefield is called triage techniques, which is doing an assessment of each person's needs and prognosis and using scarce resources with patients that are most likely to benefit from them," she said.
L.A. County Health Services Director Christina Ghaly said some hospitals are seeing patients who are still on ambulances.
"Those patients are being cared for and treated in the ambulance as if it's part of the emergency room bay," Ghaly said.
L.A. County Public Health Director Barbara Ferrer said there have been 97,472 new cases over the past seven days. "The sad reality is that all indicators show us that our situation may only get worse as we begin 2021," she said.
More Americans were hospitalized this past week than any other week of the pandemic, according to the Covid Tracking Project. And the United States reported 121,235 current Covid-19 hospitalizations on Monday, a pandemic high.
Six states set records Sunday for the most Covid-19 patients hospitalized: Alabama, California, Georgia, Mississippi, North Carolina and South Carolina. Texas hit an all-time high on Monday.
Doctors say mass holiday gatherings will lead to even more patients -- a huge problem because many hospitals are already beyond capacity.
"It's really frustrating, because if you look at the data over the last 10 days, it actually started to show some signs of light," said Dr. Jonathan Reiner, professor of medicine at George Washington University.
"Places like the Midwest, with a drop in the number of cases. Even in the Northeast. US positivity rate dropped from about 12% down to about 10%. Those are really tangible signs of a slowing of the crisis. And now there almost certainly will be another spike."
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And unlike previous holidays, the Christmas-New Year combo stretches an entire week.
"We know that after every major holiday, that there was a spike in the number of cases," emergency medicine physician Dr. Leana Wen said.
"We saw this after Memorial Day, after Fourth of July, after Labor Day. And those holidays were relatively short in comparison to Christmas and New Year's."
On top of that, the weather is much colder now -- meaning more indoor gatherings and increased risk of aerosolized spread.
ICUs are often associated with heart attacks and car accidents, but a growing number of ICU beds are occupied by Covid-19 patients.
This past week, about 40% of all ICU patients in the US had Covid-19, according to a CNN analysis of data published Monday by the US Department of Health and Human Services.
That's up from 16% in late September; 22% in late October; and 35% in late November.
And more hospitalizations inevitably precede more deaths.
The deaths of more than 63,000 Americans have been reported so far this month -- the most of any month since the pandemic began, according to Johns Hopkins University.
In just 11 months, more than 334,000 people have died from Covid-19. That means more than 1 in 1,000 Americans have died from coronavirus.
And since most Americans can't get vaccinated until well into next year, the US faces a "surge upon a surge" following holiday travel, said Dr. Anthony Fauci, director of the National Institutes of Health.
As more countries detect the highly contagious strain of coronavirus first spotted in the UK, the US Centers for Disease Control and Prevention announced new testing requirements for travelers arriving from the UK.
The new rules go into effect Monday. Passengers must have had a negative PCR or antigen test within 72 hours of boarding a flight from the UK to the US, along with documentation of their lab results.
Airlines will be required to confirm the test prior to the flight.
So far, dozens of countries have banned travelers from the UK.
All viruses mutate over time, and the novel coronavirus has mutated before. But scientists advising the UK government estimated this strain could be up to 70% more effective at spreading than others.
The companies behind the first two vaccines to gain emergency authorization in the US -- Pfizer/BioNTech and Moderna -- are testing their vaccines to confirm whether they're effective against the new strain.
Biotech company Novavax -- which announced the launch of a phase 3 trial of its Covid-19 vaccine in the US on Monday -- said it is also testing its vaccine against the UK strain.
It will take weeks for the results, the company said.
About 2.1 million Covid-19 vaccine doses have been administered in the US, according to the CDC. More than 11.4 million doses have been distributed.
Those numbers now include both the Pfizer/BioNTech and Moderna Covid-19 vaccines. And while there are lags in data reporting, federal officials had previously said they were working to distribute 20 million doses by the end of the year.
Asked about the apparent slow rollout of vaccines, Fauci said large, comprehensive vaccine programs with a new vaccine start slow before gaining momentum.
"I'm pretty confident that as we gain more and more momentum, as we transition from December to January and then February to March, I believe we will catch up with the projection," he said.
Dr. Esther Choo, a professor of emergency medicine at Oregon Health & Science University, said vaccine distribution is "just a very complicated thing."
"At every step, there's complexity and there's possibility for delay, whether it's individual state planning, allocation, training, supply of vaccine, storage ... there (are) just so many factors at this stage," Choo said.
"We need to be prepared for the fact that it is going to be a slow rollout in many places and that it will not change our behaviors or necessarily the trajectory of the pandemic in this country in the short term," Choo said.
With vaccines likely not widely available until the summer, experts have urged Americans not to let their guard down. That means continuing to wear masks, washing hands frequently, and social distancing.