Despite encouraging developments, worries persist about COVID-19 winter

Leah Giambarresi, owner of VaxinateRx, prepares a dose of the Pfizer vaccine for children age 5-11 during a vaccination clinic in Reading on Friday. Vaccinations are a key to ending the pandemic.Craig F. Walker/Globe Staff

Recent developments, including federal authorization of a COVID-19 vaccine for children 5 to 11 and the emergence of two promising pills for treatment of the disease, may have raised hopes that the coronavirus pandemic in the United States is on the wane.

But some experts are warily eyeing the approach of cold weather and the winter holidays - and urging people to get vaccinated and take precautions.

Christopher Murray, director of the University of Washington’s Institute for Health Metrics and Evaluation, said researchers were seeing increasing evidence of a surge in the Northern Hemisphere, which they believe is due to winter seasonality, waning immunity from vaccines, and people being less cautious. The question, he said, is how big the surge will be.

In the United States, he said, the institute’s closely-watched model suggests there will be a “relatively modest” surge this winter. It will be “nowhere near as large as last year,” he said, but it will still be enough to put “great pressure on hospitals” when they have to handle both COVID-19 cases and the expected influx of flu cases.

He cautioned that the IHME model may be overoptimistic because it doesn’t yet factor in waning immunity for both vaccines and prior natural infections. But he also noted that the administration of booster shots and the campaign to vaccinate children 5 to 11 could help.

Our model suggests it's a relatively modest #DeltaVariant surge in the USA this winter, nowhere near as large as last year, but still enough to put great pressure on hospitals when they have the combination of expected flu cases as well as COVID-19 (but much less than last year). pic.twitter.com/ZI1XegnaC2

— Institute for Health Metrics and Evaluation (IHME) (@IHME_UW) November 5, 2021

Dr. Ashish Jha, dean of the Brown University School of Public Health, offered a status report on the pandemic in a stream of tweets Sunday, saying the national picture had turned “mixed,” with a rapid decline in cases plateauing. That was better, he noted, than the same time last year when cases were shooting higher. He credited vaccinations.

He said the country was in a “stalemate.” People are heading indoors due to colder weather, and interacting socially more, and the Delta variant is “way worse.” But at the same time, many people have gotten their shots.

He said that in the next couple of months “social interactions will push infections up more” but a winter surge could be avoided if more adults are vaccinated, children are vaccinated, booster shots are administered, and there is “ubiquitous testing,” and masking in high-risk situations.

Quick update on state of pandemic in the US

National picture has turned mixed

Bad news: rapid declines in cases has plateaued

Over past 2 weeks, new infections flat at about 75K per day

The good news?

Early in November, we're flat

Could be much worse. Could be 2020

Thread pic.twitter.com/iSWZaddYjo

— Ashish K. Jha, MD, MPH (@ashishkjha) November 7, 2021

Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston, said in a stream of tweets last week, “We need to stop talking as though covid is over.”

“More than 40% of the country remains unvaccinated. That’s a lot of warm water for hurricane delta,” he said, referring to how hurricanes pick up strength over warm water. “I’m concerned about yet another surge beginning after Thanksgiving (just like last year).”

Hotez’s prescription to prevent a winter surge included vaccinating “pretty much all” adults and adolescents, vaccinating children, getting everyone who got a Pfizer or Moderna vaccine a third shot, and getting people vaccinated even if they have been previously infected.

We need to stop talking as though covid is over. More than 40% of the country remains unvaccinated. That’s a lot of warm water for hurricane delta. I’m concerned about yet another surge beginning after Thanksgiving (just like last year). https://t.co/R02TJNiCIt

— Prof Peter Hotez MD PhD (@PeterHotez) November 3, 2021

In a briefing Friday, Jennifer Nuzzo, epidemiology lead at the Johns Hopkins University Coronavirus Resource Center, said there were worrisome signs cropping up in the national data.

“This week compared to last week, the cases have pretty much stalled,” she said. “That’s worrisome for two reasons—one, because we like to see the declines continue, but also because where we’re stalling is at a level of weekly case numbers that are still well above what we saw at the lower periods at the end of June and in early July.”

“There are some early signs that we’re headed in the wrong direction,” she said. “It’s really important that we do something to address the stalling.”

She also raised concerns about increases in COVID cases being seen in some countries overseas, including “massive case surges” in Eastern Europe and large case increases in Africa.

She said we “need to continue to increase immunity in the population through vaccination. ... There’s still a long ways to go. The United States, as a whole, has not achieved as high a level of vaccination coverage as a number of other countries. And you know, that’s really going to put us in a much more vulnerable situation.”

The global pandemic “is very much not over and ... we must make more progress in increasing vaccine uptake not just here in the United States but globally because, again, what happens elsewhere eventually could come here,” she said.

Michael T. Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota, said in a podcast last week that it’s “hard to decipher where we’re headed.”

He said other countries that the Delta variant has swept through have had a variety of pandemic curves, with some seeing cases declining after Delta’s arrival but others, including Russia and the United Kingdom, seeing cases declining, then rising again.

“I’m not sure there’s an exact model we can really use to predict what’s going to happen. I certainly hope we will see eventual declines,” he said, “but we can also just as easily head in the other direction. ... Anyone who comes out with modeling that’s more than 30 days out from today is basing that on pixie dust.”

He pointed out that individual states in the United States are headed in different directions, with some seeing cases rising and others seeing them falling, and said “the overall US trajectory will depend on what plays out in some of these pockets of smoldering activity.” He also warned that even the most vaccinated states like those in New England still have lower levels of vaccination than some European countries currently seeing surges.

Vaccinations are key, he said. “We can’t stop when this virus decides to surge. We can’t stop it. But we can do a lot to mitigate its impact. Vaccines are what will ultimately rescue us from a lot of the damage we could expect to see during future surges,” he said.