U.S. COVID cases start to rise again as the holidays approach

It's a worrying sign for the U.S. ahead of the holiday travel season: coronavirus infections are rising in more than half of all states. Experts warn this could be the start of an extended winter surge.

The rise is a turnaround after cases had steadily declined from mid September to late October. The country is now averaging more than 83,000 cases a day — about a 14% increase compared to a week ago, and 12% more than two weeks ago.

"I hate to say it, but I suspect we're at the start of a new winter surge," says Dr. George Rutherford, an epidemiologist at the University of California, San Francisco.

Growing outbreaks in the Midwest and Northeast are most responsible for pushing up the national numbers, and that comes after many weeks of high case counts and stress on states in the mountain West where some hospitals are dealing with crisis levels of patients.

"There are still large swaths of the country under-immunized and even among states that are relatively well-vaccinated, like Colorado, New Mexico, Minnesota and Vermont, we're seeing sustained transmission," says Rutherford.

The uptick in cases hasn't yet translated into a national spike in new hospital admissions, which tend to trail a rise in infections by several weeks. However, the grim situation in some parts of the West and upper Midwest offers a concerning picture for other states where cases are now climbing.

"It's a marathon here," says Dr. Kencee Graves at the University of Utah Hospital, in Salt Lake City, Utah, who describes her state, like much of the Mountain West, as stuck in a "high plateau of a surge" where hospitals not only have an ICU full of COVID-19 patients, but also many other kinds of sick patients who need care.

Despite the concerning trends, the expectation among experts who model the pandemic's course is that a surge will not bring the same level of death and severe disease as last year.

"The vast majority of the population has some form of immunity," says Nicholas Reich, a biostatician at UMass Amherst who runs a COVID-19 forecasting model. "That feels really different about this moment — there are fewer people to infect."

How bad could it get?

The growth in cases isn't unexpected, given the patchwork of COVID-19 immunity across the U.S., where about 60% of the population is fully vaccinated.

Americans are moving around like they were before the pandemic, mask wearing is low compared to last year, people are spending more time indoors because of cooler weather, and protection against infection, both from vaccinations and prior infection, is waning, says Ali Mokdad, professor of Health Metrics Sciences at the University of Washington's Institute of Health Metrics and Evaluation.

"You put all of this together — and what you see in Europe where many countries with higher vaccination rates than the United States are seeing a surge — of course, it's going to happen," he says.

And unlike last year, the U.S. has to contend with a much more contagious version of the virus "that makes it really hard to snuff out chains of transmission," not to mention "human nature, which is wanting us to get back to pre-pandemic life," says Reich at UMass, Amherst.

Just how bad the situation gets will come down to complex dynamics around immunity. Southern states endured a brutal wave over the summer and that may have built up enough immunity from infection to shield them from another big resurgence this winter. Areas that did not face the same kind of surge, in particular states in the northern half of the country, are now dealing with an increase, but many also have the benefit of higher vaccination coverage.

"The real question is how big will it get and will it really be substantial? And my sense is in New England, it's going to hit a wall of vaccinated people," says Dr. Ashish Jha, dean of Brown University's School of Public Health.

"I think the Midwest and the Great Plains — which have lower vaccination rates but have not seen a big delta surge — they may very well end up seeing quite a few infections in the weeks and months ahead."

Even with a small surge, hospitals could still suffer

Even if hospitals see fewer COVID-19 patients overall, it's already clear that many are less prepared to handle the demands of the pandemic compared to last year.

"Every hospital I have talked to in the last month has severe shortages of staff, especially nurses," says Dr. Bruce Siegel, president of America's Essential Hospitals, which represents hundreds of public hospitals in the U.S.

At the University of Utah Hospital, Dr. Graves says their surge ICU was closed down because they couldn't staff it anymore, and last month patients were waiting on average between three to five hours for an ICU bed. "Our resources and our stamina are far less now than a year ago," she says.

In the Southwest, hospitals are also dealing with packed ICUs.

New Mexico has higher vaccination rates than many nearby states, but the state was forced to enact its crisis standards of care plan weeks ago. Some hospitals have activated those plans, but none have moved to the most extreme scenario of deciding who gets care and who doesn't, says Troy Clark, president of the New Mexico Hospital Association.

Starting in the spring, there was a "huge influx of patients that we don't normally see" with other urgent medical needs, Clark says. That has kept hospitals extremely busy heading into winter — and with no slack to accommodate the growing number of COVID-19 patients.

It's a similar situation in many states, including Arizona where hospitalizations for COVID-19 are now as high as they've been since February. "We just don't have that extra capacity for a COVID spike," says Ann-Marie Alameddin, president of the Arizona Hospital and Healthcare Association.

The upper Midwest now has some of the highest cases per capita in the country. Hospitals leaders in Minnesota are imploring people to take caution so they don't require medical care for COVID or non-COVID emergencies. "This has never been more serious," said Kelly Chandler of Itasca County Public Health, which includes the city of Grand Rapids, in a recent public statement. "We are at crisis levels of 2020, but without the same levels of COVID precautions in place."

As we head into the holidays, COVID risk increases, with more people travelling and socializing indoors. But "we also have some things that are helping, like more vaccines and kids getting vaccinated," says Brown's Ashish Jha. "So we're in a stalemate. I don't expect us to have a horrible surge, but I can certainly imagine parts of the country that see modest-sized surges as people get together and as the weather stays cold."

NPR's Rob Stein contributed to this report. [Copyright 2021 NPR]